Publications

Andreas Schiller, Sandra Jenatsch, Balthasar Blülle, Miguel Angel Torre Cachafeiro, Firouzeh Ebadi, Nasim Kabir, Mostafa Othman, Christian Michael Wolff, Aïcha Hessler-Wyser, Christophe Ballif, Wolfgang Tress, and Beat Ruhstaller

The Journal of Physical Chemistry Letters, 15, 11252−11258.

DOI: 10.1021/acs.jpclett.4c02403

This research paper investigates the impact of illumination on ion conductivity in perovskite solar cells (PSCs), highlighting the complex interplay between ionic and electronic charge transport. Using drift-diffusion simulations to reproduce experimental impedance spectroscopy results, the authors discovered that the increase in capacitance observed at low frequencies under illumination is mainly caused by changes in electronic currents that emerge naturally as a consequence of the mixed electronic-ionic conduction in the perovskite. The simulations show how the changes in the alternating electronic currents occur due to the screening of the alternating electric field by oscillating ions within the active layer of the PSCs. 

A key contribution of this study is the introduction of a novel characterization technique to detect the presence of photo-enhanced ion conductivity. This technique is based on analyzing the frequency shift of the capacitance onset at different illumination intensities. The researchers extracted the frequency at which the capacitance reaches a specific value between the plateaus at lower and higher frequencies. By plotting the difference in the extracted frequency at various illumination intensities compared to in the dark, they observed distinct qualitative differences in the frequency shift patterns, depending on the presence of a photoconductive effect on the ions. 

The findings revealed that if there is no photoconductive effect, the derivative of the frequency shift decreases at lower illumination intensities. In contrast, in simulations mimicking a photoconductive effect, the derivatives increase with decreasing illumination intensity. To capture these distinct patterns, the technique requires a series of capacitance measurements over several orders of magnitude in illumination intensity. The illumination intensity range should be carefully chosen to observe both the constant derivative decrease and the change in the derivative at lower intensities. 

The researchers successfully applied this method to four different PSCs with varying active materials, confirming the presence of photo-enhanced ion conductivity in all the devices. This novel technique offers a simple and effective way to detect photo-enhanced ion conductivity in PSCs. It utilizes impedance measurements on fully integrated devices, making it practical for real-world applications. By contributing to a better understanding of the complex interplay between ionic and electronic charge transport, this technique can ultimately lead to improved device performance and stability. 

Fluxim's Setfos simulation software and Paios measurement platform were crucial to this research. Setfos enabled the creation of a drift-diffusion model of a PSC, simulating the behavior of the active layer—treated as a mixed electronic-ionic conductor—under different illumination conditions. This simulation was instrumental in understanding the influence of ionic charge carriers on capacitance and conductance. Paios, equipped with its calibrated white LED light source, was used to perform Electrochemical Impedance Spectroscopy (EIS) measurements on the PSCs to detect photoconductive effects on the ions. 

These findings emphasize the need for further research to develop a complete understanding of the phenomenon, as the interaction between ionic and electronic charge transport plays a significant role in the performance and stability of PSCs.

Lin, M. Y., Li, Q.-T., & Li, Y.-L. (2024).

IEEE Photonics Technology Letters, 36, 1730–1733. https://doi.org/10.1109/LPT.2024.3450713

This study investigates the impact of black matrix (BM) width on the performance of quantum dot full-color displays. The authors use theoretical calculations and simulations to evaluate how BM width affects crosstalk, the aliasing effect, and color gamut. They find that increasing the BM width from 0 nm to 25 nm can eliminate crosstalk between subpixels and significantly reduce the aliasing effect. This leads to a substantial improvement in color gamut, with the display featuring an Ag/ZnO/Ag structure achieving a color gamut ratio of 100.65% Adobe RGB and a coverage of 87.17%. The study highlights the importance of BM width optimization in quantum dot display design for achieving high image quality and wide color gamut. This research is particularly relevant for applications like small panels and head-mounted displays.

How Setfos was used

Setfos was used to model and optimize all of the MIM (metal-insulator-metal) layer models and to calculate the transmitted spectrum for the subpixels with the MIM layer.

Aeberhard, U., Natsch, N., Schneider, A., Zeder, S.J., Carrillo-Nuñez, H., Blülle, B. and Ruhstaller, B. (2024),

Sol. RRL 2400492.

https://doi.org/10.1002/solr.202400492

This research paper examines reverse-bias breakdown in all-perovskite tandem solar cells, particularly under partial shading conditions, and highlights how nonuniform active area quality, such as variations in mobile ion concentration, can impact their performance. The study uses a multi-scale simulation approach to demonstrate that an increase in mobile ion density significantly reduces the breakdown voltage and can lead to localized current hot spots in large-area modules. The authors suggest that these hot spots, caused by fluctuating mobile ion concentration, are potential degradation centers in the solar cells. They also suggest further investigation into factors like unintentional doping and additional breakdown mechanisms to better understand and improve the performance of these solar cells.

How SETFOS Was Used to Study Reverse-Bias Breakdown

The authors of the research paper use the device simulation tool SETFOS to perform cell-level simulations on all-perovskite tandem solar cells. Here's a breakdown of its role:

Drift-diffusion Simulation: SETFOS is used to simulate the behavior of charge carriers within the solar cell under a large reverse-bias voltage. This helps researchers visualize the band profile, or the energy levels of electrons within the device's various layers.

Mobile Ion Consideration: The simulations in SETFOS incorporate the effects of mobile ions within the perovskite layer, a crucial aspect that influences the breakdown voltage.

Coupling with Quantum Transport Simulation: The data from SETFOS, including the band profile and quasi-Fermi levels, are then used as input for a separate quantum transport simulation tool, PVnegf. This allows for a microscopic examination of the tunneling breakdown current.

Iterative Analysis: The tunnel generation rates, calculated in PVnegf, are fed back into SETFOS. This iterative process, with information exchanged between SETFOS and PVnegf, continues until the tunneling current converges, providing an accurate representation of the breakdown phenomenon.

Generating JV Curves: Through this coupled simulation approach, SETFOS ultimately helps generate current density-voltage (JV) curves for the all-perovskite tandem solar cell, even under reverse-bias conditions. These JV curves are essential for understanding how the device performs near its breakdown voltage.

In summary, SETFOS acts as the foundation for the cell-level simulations, providing crucial data about charge transport and mobile ion behavior, which is then combined with quantum transport calculations to comprehensively study reverse-bias breakdown in all-perovskite tandem solar cells.

Using Laoss to Simulate Large-Area Solar Module Behavior

Simon J. Zeder, Balthasar Blülle, Beat Ruhstaller, and Urs Aeberhard,  Opt. Express 32, 34154-34171 (2024)

https://doi.org/10.1364/OE.522953

This paper presents a multiscale optical model developed to accurately quantify photon recycling (PR) and luminescent coupling (LC) in optoelectronic devices such as solar cells and LEDs. Photon recycling, the process of photon emission, re-absorption, and re-emission, can significantly enhance device efficiency, particularly in materials like GaAs, metal halide perovskites and even crystalline silicon. To accurately account for re-absorption effects, the model treats light absorption and emission equally, considering the full spectrum of internal modes within the device. This approach stands out from conventional methods, which focus solely on exterior-coupled modes.

The framework integrates two key propagation models: 

Coherent Wave-Optical Model: Applied to thin-film layers where light interference effects are significant, avoiding unphysical divergencies for emitters embedded in absorbing media and ensuring consistency with detailed balance principles. 

Incoherent Ray-Optical Model: Used for optically thick layers where coherence is lost, treating phase relations as irrelevant. 

The model also accounts for light scattering at textured surfaces, essential for devices like perovskite –silicon tandem solar cells. By merging these approaches, the paper provides a robust framework for computing local emission, re-absorption, and energy flux rates in devices with complex structures. Importantly, this allows for a detailed understanding of the impact of photon recycling on device performance, including enhanced external quantum efficiency (EQE) in LEDs and increased open-circuit voltages in solar cells. 

The model is validated through comparisons with analytical solutions, showing excellent agreement, and applied to a textured perovskite solar cell showcasing its capabilities. This validation confirms that the model can reliably be applied to real-world devices, offering a powerful tool for optimizing the performance of next-generation optoelectronic systems. 

Key Takeaways: 

∙ Comprehensive multiscale approach merging coherent and incoherent light models. 

∙ Applicability to complex textured devices like perovskite solar cells and LEDs. 

∙ Quantification of local re-absorption and energy flux rates. 

∙ Validation through comparison with analytical solutions. 

W.-H. Hu, F. Nüesch, D. Giavazzi, M. Jafarpour, R. Hany, M. Bauer, . Adv. Optical Mater. 2024, 12, 2302105. https://doi.org/10.1002/adom.202302105

This research focuses on using squaraine dyes in single-component shortwave infrared (SWIR) photodiodes and upconversion photodetectors. These devices achieve over 40% external quantum efficiency beyond 1000 nm through field-assisted exciton dissociation. By integrating SWIR photodiodes with organic LEDs, they convert SWIR photons into visible light, offering an alternative to inorganic imaging technologies.

Key Points

Efficient SWIR Detection: Over 40% external quantum efficiency beyond 1000 nm.

Field-Assisted Charge Generation: Enables efficient exciton dissociation.

Upconversion Photodetectors: Combine SWIR photodiodes with OLEDs for visible light emission.

Simplified Fabrication: Single-component layers enhance stability and reduce complexity.

Inorganic Alternative: Potential replacement for existing inorganic SWIR imaging technologies.

How Setfos Was Used

Setfos was employed for optical simulations, analyzing device layer properties using refractive index and extinction coefficient values. These simulations optimized light absorption and exciton generation, crucial for efficient SWIR detection and upconversion.

C.-H. Chen, M.-H. Yu, Y.-Y. Wang, Y.-C. Tseng, I. Chao, I. Ni, B.-H. Lin, Y.-J. Lu, C.-C. Chueh, Small 2024, 20, 2307774. https://doi.org/10.1002/smll.202307774

The research investigates the enhancement of 2D tin-based pure red perovskite light-emitting diodes (PeLEDs) using a dual-additive approach involving natural antioxidants and cyclic molecular additives. Specifically, ascorbic acid (VitC) is used to prevent the oxidation of Sn²⁺ to Sn⁴⁺ and improve film quality, while 18-Crown-6 is added to capture excess ions and synergistically reduce nonradiative recombination pathways. This combination significantly improves the PeLEDs' performance, achieving a maximum external quantum efficiency of 1.87%, which is approximately nine times higher than the pristine device. The study highlights the potential of environmentally friendly additives to enhance the stability and efficiency of Sn-based perovskite films for sustainable optoelectronic applications.

Use and Value of Paios

Paios, the all-in-one characterization tool from Fluxim, was employed for capacitance-voltage (C-V) measurements and transient electroluminescence (EL) decay measurements.

The C-V measurements provided insights into the charge injection and recombination processes in the PeLEDs, indicating that the 25CC film (with both VitC and 18-Crown-6) had the highest charge transfer efficiency and lowest trap density.

Transient EL measurements revealed that the 25CC devices had the fastest response time and lowest trap density, confirming the superior carrier mobility and performance

Raphael F. Moral, Carlo A. R. Perini*, Tim Kodalle, Ahyoung Kim, Finn Babbe, Nao Harada, Javid Hajhemati, Philip Schulz, Naomi S. Ginsberg, Shaul Aloni, Craig P. Schwartz, Juan-Pablo Correa-Baena*, and Carolin M. Sutter-Fella*

ACS Energy Lett. 2024, 9, 6, 2703–2716

Publication Date: May 14, 2024

https://doi.org/10.1021/acsenergylett.4c00728

This study investigates ionic dynamics at 2D/3D halide perovskite interfaces in solar cells, revealing that light and heat induce ion migration. Phenethylammonium halide salts enhance efficiency and stability, with specific migration patterns and phase distributions observed under thermal treatment, impacting photovoltaic performance.

How Litos Lite was used

The photovoltaic performance assessment was conducted utilizing a Fluxim Litos Lite arrangement, which featured a Wavelabs Sinus-70 AAA solar simulator that produced an AM1.5 spectrum for excitation purposes. The current−voltage (J−V) attributes were obtained through both forward and reverse scans, each performed at a scan rate of 50 mV s−1. Stabilized power output measurements were completed utilizing a maximum power point (MPP) tracking algorithm over a span of 60 s.

Hang Hu; An, Sophie X.; Li, Yang; Orooji, Seyedamir; Singh, Roja; Schackmar, Fabian; Laufer, Felix; Jin, Qihao; Feeney, Thomas; Diercks, Alexander; Gota, Fabrizio; Moghadamzadeh, Somayeh; Pan, Ting; Rienäcker, Michael; Peibst, Robby; Nejand, Bahram Abdollahi; Paetzold, Ulrich W.

Energy Environ. Sci.2024,17, 2800-2814.

DOI: 10.1039/D3EE03687A.

In this paper Prof. Ulrich W. Paetzold's team at KIT achieved a record 24.4% efficiency in triple junction perovskite solar cells using a new vacuum-assisted growth process. The mid-subcell, made of FAPbI3, ensures thermal stability and ideal interfaces.

How Paios was used

The researchers used the PAIOS system for various measurements including electrical impedance spectroscopy, transient photovoltage, electroluminescence, photoluminescence imaging, Mott-Schottky, dark J–V curves, and space-charge-limited current, enabling efficient, streamlined analysis and characterization of their triple-junction perovskite solar cells .

Morteza Najarian, A., Vafaie, M., Chen, B. et al.

Nat Rev Phys6, 219–230 (2024).

https://doi.org/10.1038/s42254-024-00699-z

This paper from the research team at the University of Toronto reviews materials suitable for high-speed photodetectors, emphasizing their photophysical characteristics. It covers material classes such as organic semiconductors, perovskites, and quantum dots, discussing their performance metrics, advantages, and limitations for applications in high-speed optical communication and imaging technologies.

How Setfos was used

Simulations to understand the dynamics of electron traps were conducted using SETFOS software.

Sami Toikkonen, G. Krishnamurthy Grandhi, Shaoyang Wang, Bora Baydin, Basheer Al-Anesi, L. Krishnan Jagadamma, Paola Vivo.

Adv Devices Instrum.2024;5:0048.

DOI:10.34133/adi.0048

The study investigates the necessity of doping Spiro-OMeTAD in lead halide perovskite (LHP) indoor photovoltaics (IPVs). It concludes that undoped Spiro-OMeTAD can achieve high efficiency and stability under low-light conditions, rivaling doped counterparts, suggesting that dopants may not be essential for effective IPV performance.

How Litos Lite was used

Litos Lite was utilized to perform J–V reverse and forward sweeps (scan rate 50 mV s−1), maximum power point (MPP) tracking, and stable power output (SPO) measurements on the prepared photovoltaic cells. These measurements were conducted under both simulated sunlight (AM 1.5G, 1-Sun, 100 mW cm−2) and indoor WLED illumination (5,000 lux, ≈1.60 mW cm−2) in N2 atmosphere. The indoor MPP tracking was performed either under continuous illumination or in 8-hour light–16-hour dark cycles .

How Paios was used

Transient photovoltage and transient photocurrent measurement were carried out with the all-in-one characterization platform, Paios.

Othman, M., Jeangros, Q., Jacobs, D. A., Futscher, M. H., Zeiske, S., Armin, A., Jaffrès, A., Kuba, A. G., Chernyshov, D., Jenatsch, S., Züfle, S., Ruhstaller, B., Tabean, S., Wirtz, T., Eswara, S., Zhao, J., Savenije, T. J., Ballif, C., Wolff, C. M., & Hessler-Wyser, A. (2024). Energy & Environmental Science. The Royal Society of Chemistry.

DOI: https://doi.org/10.1039/D4EE00901K

This study investigates the effects of cationic alloying in cesium-formamidinium perovskite films on optoelectronic properties and solar cell performance. It finds that precise Cs+ tuning minimizes structural faults and enhances photoconductivity, with encapsulated devices maintaining 85% of initial efficiency after 1400 hours under continuous illumination, providing insights into defect tolerance and stability mechanisms in perovskite materials.

Fluxim's Research Tools

In the study, Fluxim's Paios system was used for conductivity measurements, and Litos for accelerated aging tests under thermal and photonic stress, evaluating the stability of perovskite solar cells.

Cachafeiro, Miguel A Torre, Naresh Kumar Kumawat, Feng Gao and Wolfgang Tress.

National Science Review (2024): nwae128

https://doi.org/10.1093/nsr/nwae128

The paper investigates the pulsed operation of perovskite LEDs (PeLEDs), focusing on the role of mobile ions in transient electroluminescence. Drift-diffusion simulations demonstrate how mobile ions affect the TrEL signals and device performance, with findings crucial for optimizing PeLED design and function.

How Setfos was used

The Setfos software was used to perform drift-diffusion simulations that modeled the behavior of mobile ions in perovskite LEDs. It analyzed their impact on transient electroluminescence and device performance, helping to elucidate the mechanisms affecting light emission during pulsed operation.

Almora, O., López-Varo, P., Escalante, R., Mohanraj, J., Marsal, L. F., Olthof, S., & Anta, J. A. (2024). arXiv:2402.00439 [physics.app-ph]

https://doi.org/10.48550/arXiv.2402.00439

The paper analyzes degradation in perovskite solar cells using impedance spectroscopy, focusing on NiOx passivation. It identifies how interface treatments influence device performance, with some treatments stabilizing and others inducing degradation. Simulation tools model transport properties to understand these effects.

How Setfos Was Used

Fluxim's Setfos simulation software was employed to model the transport properties and electrical responses of passivated-NiOx perovskite solar cells. This facilitated the understanding of how modifications at the hole transport layer-perovskite interface, due to various passivation methods, impact the cells' performance and operational stability.

Hou, Min-Chih and Luo, Dian and Huang, Yu-Ting and Liu, Shun-Wei and Lu, Chin-Wei and Chang, Chih-Hao and Su, Hai-Ching

Available at SSRN:

http://dx.doi.org/10.2139/ssrn.4608462

The study explores optimizing light extraction in light-emitting electrochemical cells (LECs) by adjusting the concentration of small TiO2 nanoparticles in a diffuser film. Enhanced roughness and appropriate refractive index improve light outcoupling, offering potential for higher device efficiencies in LEC lighting applications.

How Setfos was used

Fluxim's Setfos software was crucial in simulating light extraction efficiencies from LECs. By varying the TiO2 nanoparticle concentration in diffuser films, Setfos helped ascertain the optimal conditions for light outcoupling, demonstrating a significant enhancement in device performance with properly configured diffuser films.

A Boron, Nitrogen, and Oxygen Doped π-Extended Helical Pure Blue Multiresonant Thermally Activated Delayed Fluorescent Emitter for Organic Light Emitting Diodes That Shows Fast kRISC Without the Use of Heavy Atoms.

R. W. Weerasinghe, S. Madayanad Suresh, D. Hall, T. Matulaitis, A. M. Z. Slawin, S. Warriner, Y.-T. Lee, C.-Y. Chan, Y. Tsuchiya, E. Zysman-Colman, C. Adachi,

Adv. Mater. 2024, 2402289. https://doi.org/10.1002/adma.202402289

This study presents a boron, nitrogen, and oxygen-doped π-extended helical emitter for OLEDs that emits pure blue light efficiently without heavy metals. It demonstrates fast reverse intersystem crossing and high photoluminescence quantum yield, achieving narrow emission spectra close to the BT.2020 standard.

How Setfos was used

Setfos was used to analyze the orientation of transition dipole moments (TDM) within the films containing the MR-TADF emitter, f-DOABNA. This analysis is crucial for assessing how the TDM are oriented relative to the film surface, which affects the light outcoupling efficiency—a key factor in enhancing the performance of OLED devices.

Specifically, Setfos helped determine the horizontal-dipole ratios of f-DOABNA doped in different host materials. These ratios, varying between values indicative of perfectly horizontal to vertical orientation, provide insight into how efficiently the emitted light can be outcoupled from the OLED device. The results from Setfos showed that the emitter had a significant degree of horizontal alignment, especially in one host material, indicating better light outcoupling efficiency in that configuration.

Thiesbrummel, J., Shah, S., Gutierrez-Partida, E. et al.

Nat Energy (2024).

https://doi.org/10.1038/s41560-024-01487-w

The study reveals that the dominant factor in the degradation of perovskite solar cells (PSCs) under operational conditions is mobile ion-induced internal field screening, significantly reducing efficiency mainly due to current density reduction, without major bulk or interface quality degradation.

How Setfos was used

Setfos was used to simulate the impact of increasing mobile ion density on PSC performance, demonstrating that higher ion density leads to enhanced internal field screening, reducing charge extraction efficiency and contributing significantly to early degradation losses in PSCs.

C.-H. Chen, M.-H. Yu, Y.-Y. Wang, Y.-C. Tseng, I. Chao, I. Ni, B.-H. Lin, Y.-J. Lu, C.-C. Chueh,

Small 2024, 2307774.

https://doi.org/10.1002/smll.202307774

This paper presents a method to significantly enhance the performance of 2D tin-based red perovskite LEDs through the use of natural antioxidants and cyclic molecular additives, particularly ascorbic acid and 18-Crown-6. These additives mitigate the oxidation of Sn2+ to Sn4+ and improve film quality, leading to a substantial increase in external quantum efficiency (EQE), purer color, and better bias stability. The study showcases a potential dual-additive approach for advancing 2D Sn-based perovskite LEDs towards sustainability and efficiency.

How Paios was used

Paios was utilized for comprehensive electrical characterization, including space-charge-limited current measurements, electrochemical impedance spectroscopy, capacitance-voltage analysis, and transient electroluminescence studies. These tests revealed that the additives effectively reduced trap densities and leakage currents, improved carrier transport, and enhanced charge transfer efficiency, corroborating the additives' impact on device performance and stability.

Fangfang Yuan, Yuncai Liang, Zhipeng Miao, Ting Zhang, Rudai Zhao, Sihui Peng, Yunhang Xie, Wenlong Liang, He Zhu, Pengwei Li, Yiqiang Zhang, and Yanlin Song

Chemistry of Materials 2024 36 (3), 1621-1630

https://doi.org/10.1021/acs.chemmater.3c02960

This paper reports the development of highly efficient and stable 2D Dion-Jacobson perovskite solar cells using oxygen-containing diamine cations (OBEAI). These cations optimize charge transfer properties, leading to a power conversion efficiency (PCE) of up to 18.81% and outstanding stability, maintaining over 90% of initial performance after 2000 hours.

How Paios was used

Paios was used to assess the charge transport and recombination dynamics in perovskite films, highlighting improved electron transport, reduced recombination, and enhanced charge collection efficiency after OBEAI modification.

Nayrim Brizuela Guerra, João Victor Morais Lima, Natan Luis Nozella, Miguel Henrique Boratto, João Vitor Paulin, and Carlos Frederico de Oliveira Graeff

ACS Applied Bio Materials Article ASAP

https://doi.org/10.1021/acsabm.3c01166

This study explores increasing the conductivity of synthetic melanin derivatives through electrochemical doping, revealing that different anions can significantly affect charge transport. The most effective doping achieved with ClO4− anions, enhanced electronic transport to levels surpassing some reported melanin devices, suggesting a promising method for tuning melanin's conductivity for bioelectronics applications.

How Paios was used

Paios was employed for electrical characterizations before and after electrochemical treatments, allowing the investigation of charge transport and recombination dynamics. This contributed to understanding the improved photovoltaic performance due to enhanced electron transport and reduced recombination, crucial for developing efficient melanin-based devices.

Zheng Zhang, Jiaqi Liu, Huan Bi, Liang Wang, Qing Shen, Shuzi Hayase,

Chemical Engineering Journal, Volume 483, 2024, 149345, ISSN 1385-8947,

https://doi.org/10.1016/j.cej.2024.149345.

This study achieved over 14% efficiency in highly reproducible Sn perovskite solar cells by utilizing polysilanes, particularly polymethyl-phenyl-silane (PMPS), for defect passivation and morphology improvement. The application of PMPS enhanced surface quality, grain size, and reduced Sn4+ defects, leading to significant improvements in device efficiency and stability.

How Paios was used

Paios was used to evaluate charge transport and recombination dynamics, providing insights into the improved photovoltaic performance through enhanced electron transport, reduced recombination, and increased charge collection efficiency.

Yeonghoon Jin, Hyung Suk Kim, Donggyun Lee, Chihaya Adachi, Seunghyup Yoo, and Kyoungsik Yu

The Journal of Physical Chemistry C 2024 128 (4), 1755-1761

https://doi.org/10.1021/acs.jpcc.3c06330

This study introduces a rigorous analysis comparing distributed and concentrated dipole models in organic thin films using angle-dependent photoluminescence, highlighting inaccuracies in TDM orientation assumptions for thick emitter layers. It emphasizes considering the spatial distribution of TDMs, especially as film thickness increases, for precise OLED optical design.

How Phelos was used

Phelos was utilized for optical characterization via angle-dependent photoluminescence spectroscopy, aligning experimental setups and validating the necessity of considering distributed dipole models for accurate TDM orientation analysis in thick films.

T. Lee, M. Lee, K. Kim, H. Lee, S.-Y. Yoon, H. Yang, S. Yu, J. Kwak, Adv. Optical Mater. 2024, 2302509.

https://doi.org/10.1002/adom.202302509

This study presents angle-independent top-emitting quantum dot light-emitting diodes (QLEDs) featuring a solution-processed subwavelength scattering–capping layer (SCPL) composed of ZnO nanoparticles. This SCPL enhances light extraction and minimizes angle-dependent color shifts, achieving a 44% improvement in external quantum efficiency without perceivable spectral shifts across viewing angles. The dual functionality of the SCPL, serving both as a capping and scattering layer, introduces a simplified, cost-effective method for fabricating high-performance, angle-stable QLED displays.

How Setfos was used

Setfos was utilized to optimize the microcavity structure of blue-emitting QLEDs by adjusting the thickness of hole transport and electron transport layers, aiming for maximum light extraction efficiency and luminance. The tool's simulations guided the experimental verification of the device's optoelectronic performance, helping to achieve superior efficiency and color stability by precisely controlling the thickness of the scattering–capping layer (SCPL).

Zbinden, O., Knapp, E. and Tress, W. (2024), Sol. RRL 2300999.

https://doi.org/10.1002/solr.202300999

his study demonstrates how machine learning (ML) can pinpoint the parameters limiting efficiency in perovskite solar cells (PSCs) by analyzing current density–voltage curves from simulated devices. Over 11,000 simulated curves, varying 20 physical parameters related to charge transport and recombination, trained ML models to classify limiting parameters with over 80% accuracy. Random Forests showed the best performance, identifying key parameters like short-circuit current density, open-circuit voltage, and fill factor as critical for predictions. Applied to real device data, the model accurately identified efficiency-limiting factors, validating the approach's utility in guiding performance improvements and understanding device behavior, particularly during degradation. This methodology promises significant time and resource savings by reducing trial-and-error in PSC optimization.

How Setfos was Used

Setfos was used to generate about 11,150 current density–voltage (J–V) curves for perovskite solar cells by systematically varying one device parameter at a time, facilitating the training of machine learning algorithms to identify performance-limiting parameters based on these simulations.

E. Benvenuti, A. Lanfranchi, S. Moschetto, M. Natali, M. Angelini, P. Lova, F. Prescimone, V. Ragona, D. Comoretto, M. Prosa, M. Bolognesi and S. Toffanin,

J. Mater. Chem. C, 2024,

DOI: 10.1039/D3TC04321E.

This paper presents the development of an all-organic, on-chip integrated system for fluorescence detection, combining organic photodiodes (OPDs), organic light-emitting diodes (OLEDs), and a polymeric distributed Bragg reflector (DBR) filter. By integrating these components on a single substrate, the system offers a compact and efficient solution for fluorescence sensing, which is crucial for applications ranging from food safety to environmental monitoring. The use of organic materials allows for low-cost, flexible sensors that can be easily produced and deployed. The paper demonstrates that this integrated approach significantly enhances the optical efficiency and sensitivity of the fluorescence sensor, making it capable of detecting concentrations as low as 9.2 μM of the model dye Rhodamine 700. This advancement represents a significant step towards the development of portable, high-performance sensors for point-of-need applications​

How Sefos was used

Setfos was used to design the OLED structure to achieve an efficient and narrow phosphorescent emission, crucial for the integrated fluorescence sensor's performance. The simulation helped in fine-tuning the composition and thickness of the OLED's interlayers, including an organic index matching layer, to enhance light extraction and emission characteristics tailored to the absorption spectrum of the fluorescent dye, Rhodamine 700.

Xu, Ting and Jiang, Haixiao and Dong, Haojie and Zhao, Kele and Liang, Xiao and Sun, Yanqiu and Ding, Lei and meng, lingqiang and Meng, Hong,

Available at SSRN: https://ssrn.com/abstract=4610784

The study presents a novel approach to enhance blue MR-TADF OLEDs' efficiency and color purity using tandem device structures. By employing TBN-TPA as the blue MR-TADF material in tandem OLED devices, narrow-band emission and high color purity were achieved through optical interference and microcavity effects, aligning with BT 2020 standards. This advancement underscores the potential of tandem architectures and MR-TADF emitters in developing high-performance OLEDs with both high efficiency and wide color gamut, suggesting further research in optimizing tandem structures and MR-TADF materials.

How Setfos was used

Setfos software was utilized to simulate optical and electrical characteristics of OLED devices, particularly analyzing spectral enhancements, microcavity effects, and interference within the tandem OLED structures, to predict and understand device performance improvements, including color purity and efficiency.

Valastro, S., Calogero, G., Smecca, E., Bongiorno, C., Arena, V., Mannino, G., Deretzis, I., Fisicaro, G., La Magna, A. and Alberti, A. (2024), Sol. RRL 2300944.

https://doi.org/10.1002/solr.202300944

The research demonstrates printable carbon-based perovskite solar cells infiltrated with CsPbI3:EuCl3 outperform AVA-MAPbI3 cells, showcasing reduced hysteresis, stable efficiency under continuous light, and notable durability with multiple reusability cycles. Achieving a peak power conversion efficiency of 16.72%, the CsPbI3:EuCl3 variant emerges as a promising candidate for sustainable and efficient photovoltaic technologies, with implications for enhancing the environmental sustainability of solar energy generation​

How Setfos was used

Setfos tool was utilized for 1D transient-mode electro-optical simulations of the fabricated mesoporous carbon perovskite solar cells (mC-PSCs), incorporating both anion and cation migration within the active regions. This involved simulating the charge generation profile using the transfer-matrix method, calibrated with wavelength-dependent complex refractive indices of all layers, and coupling it with a drift-diffusion charge transport solver to account for charge trapping, recombination, and ion migration. The simulations aimed to replicate the measured J–V curves' main features, with layer-specific electrical parameters calibrated based on reasonable initial values from literature.

Ying Zhang, Wanyuan Deng, Christopher E. Petoukhoff, Xinxin Xia, Yongwen Lang, Hao Xia, Hua Tang, Hrisheekesh Thachoth Chandran, Sudhi Mahadevan, Kuan Liu, Patrick W.K. Fong, Yongmin Luo, Jiaying Wu, Sai-Wing Tsang, Frédéric Laquai, Hongbin Wu, Xinhui Lu, Yang Yang, Gang Li

Joule, 2024, , ISSN 2542-4351,

https://doi.org/10.1016/j.joule.2023.12.009.

This study introduces a guest polymer-tailored layer-by-layer (GPT-LBL) method for creating organic solar cells (OSCs) with a p-i-n microstructure, improving vertical composition and molecular organization control. By monitoring pre-aggregation behaviors of non-fullerene acceptors, this approach enhances charge transport, reduces energy loss, and increases efficiency. A resulting GPT-LBL OSC demonstrated a remarkable power conversion efficiency (PCE) of 19.41% (certified 19.0%), and a large-area device showed a PCE of 17.52% using green-solvent processing, marking a significant advancement in scalable and environmentally friendly OSCs.

How Paios was used

Photo-CELIV measurements were carried out with Paios.

C.-H. Chen, M.-H. Yu, Y.-Y. Wang, Y.-C. Tseng, I. Chao, I. Ni, B.-H. Lin, Y.-J. Lu, C.-C. Chueh,

Small 2024, 2307774.

https://doi.org/10.1002/smll.202307774

This research explores the use of natural antioxidants as additives to improve the fabrication of environmentally friendly Sn-based perovskite films, tackling oxidation and crystallization challenges. Ascorbic acid is highlighted for its effectiveness against oxidation, and when combined with 18-Crown-6, it enhances 2D red Sn-based PeLED performance, increasing efficiency, color purity, and stability, showcasing a sustainable dual-additive approach for optoelectronic applications.

How Paios was used

Impedance and TEL to demonstrate better transport with additives.

Nguyen, H., Penukula, S., Mahaffey, M. et al. MRS Communications (2024).

https://doi.org/10.1557/s43579-023-00510-7

This study investigates how polyvinylpyrrolidone (PVP) affects cesium-based lead halide perovskites, focusing on phase, morphology, film stress, and ion concentration during aging. Using PVP in CsPbI3 enhances film stability by inducing compressive stress, with negligible impact on bandgap and ion behavior under aging conditions.

How Paios was used

The all in one characterization tooll, Paios, was used to analyse ion concentration with transient current measurements.

X. Zhang, J. Ràfols-Ribé, J. Mindemark, S. Tang, M. Lindh, E. Gracia-Espino, C. Larsen, L. Edman, Adv. Mater. 2024, 2310156.

https://doi.org/10.1002/adma.202310156

The paper by Zhang et al. investigates the decrease in emission efficiency at higher currents in light-emitting electrochemical cells (LECs). It focuses on identifying and quantifying the major factors causing this efficiency drop, such as outcoupling efficiency and exciton quenching. The study presents a method to analyze these factors, contributing to the design of more efficient, high-luminance LEC devices.

How Setfos was used

Setfos was used for modeling in the study. This software simulated the structure of the light-emitting electrochemical cell (LEC) device, including various components like the glass substrate, ITO anode, active material, and Al cathode. The software modeled excitons as emissive electrical dipoles. It was particularly used for simulating the electroluminescence (EL) spectra and EL intensity to determine the position of the emissive p-n junction in the device, using a delta function exciton distribution in a transparent, non-doped active material with the wavelength-dependent refractive index of pristine Super Yellow

S. Ravishankar, L. Kruppa, S. Jenatsch, G. Yan and Y. Wang, Energy Environ. Sci., 2024,

DOI: 10.1039/D3EE02013D.

The paper discusses a novel method for analyzing solar cell operation, focusing on perovskite solar cells (PSCs). It addresses a gap in understanding the equivalence of time-domain and frequency-domain data in solar cell analysis. The study introduces a new approach to extract a previously inaccessible time constant from frequency domain data, which correlates with charge extraction speed in transient measurements. This method is validated through simulations and experimental data, offering a more comprehensive understanding of charge carrier dynamics in solar cells, particularly regarding charge collection efficiency.

How Setfos was used

SETFOS was utilized in the paper for conducting drift-diffusion simulations. These simulations were part of the study's methodology to characterize perovskite solar cells (PSCs) using various techniques, including transient photovoltage (TPV), transient photocurrent (TPC), intensity-modulated photovoltage spectroscopy (IMVS), intensity-modulated photocurrent spectroscopy (IMPS), and impedance spectroscopy (IS)​

Lei Gao, Helin Wang, Qiang Guo, Zongtao Wang, Fan Yuan, Erjun Zhou,

Chemical Engineering Journal, Volume 480, 2024, 148277, ISSN 1385-8947,

https://doi.org/10.1016/j.cej.2023.148277.

The paper presents a novel D-A-D typed fused-ring perylene diimide (PDI)-based organic small molecule, PDTI1, as a cathode interface layer (CIL) for efficient inverted perovskite solar cells (PSCs). PDTI1 enhances electron transport, improves power conversion efficiency (PCE) to 24.64%, and offers better stability compared to control devices. This work demonstrates PDTI1's superiority as a CIL, providing an alternative for high-efficiency PSCs.

How Paios was used

Paios was used in the study for conducting two key tests: Transient Photocurrent (TPC) and Transient Photovoltage (TPV). These tests were performed in the dark to analyze the characteristics of the solar cells​.

Sota Kikuchi, Takayuki Okamoto, Mengmeng Chen, Shen Qing, Shuzi Hayase,

Next Materials, Volume 3, 2024, 100098, ISSN 2949-8228,

https://doi.org/10.1016/j.nxmate.2023.100098.

The paper presents a study on improving the efficiency of lead-free ASnI2Br perovskite solar cells using phenyltrihydrosilane (PhSiH3) passivation. This passivation effectively reduces Sn4+ and creates a hydrophobic surface, enhancing the solar cells' efficiency from 3.65% to 5.50%. The process involves passivating the film surface with PhSiH3 solution, which decreases Sn4+ concentration on the perovskite film surface and makes the surface hydrophobic, resulting in better contacts with the C60 layer. The study demonstrates the effectiveness of PhSiH3 treatment in enhancing solar cell performance.

How Paios was used

Paios was utilized specifically for impedance measurement and analysis. This all-in-one characterization tool helped the researchers in assessing the electrical properties of the perovskite solar cells, which is crucial for understanding and enhancing their performance​.

hunyan Lu, Xiaodong Li, Haobo Yuan, Wenxiao Zhang, Xuemin Guo, Acan Liu, Hui Yang, Wen Li, Zhengbo Cui, YuYang Hu, Junfeng Fang,

Chemical Engineering Journal, Volume 480, 2024, 147267, ISSN 1385-8947,

https://doi.org/10.1016/j.cej.2023.147267

The paper introduces a back-surface field in inverted CsPbI3 perovskite solar cells using 4-Imidazoleethylamine (4-IEA) treatment to improve efficiency and stability. The treatment upshifts the Fermi level at the CsPbI3 surface, creating an extra back-surface field that aligns with the built-in potential of the solar cells. This alignment reduces energy loss and facilitates electron extraction at the CsPbI3/electron transporting layer interface. Additionally, 4-IEA passivates interfacial defects due to its Lewis base-acid interaction with CsPbI3. The result is a power conversion efficiency of 20.22% and good operational stability, retaining over 70% efficiency after 200 hours at 65℃.

How Paios was used

Paios was employed for transient photocurrent decay (TPC) and transient photovoltage (TPV) decay measurements. These measurements were crucial in understanding the dynamic charge transport process in the solar cells. The TPC and TPV results demonstrated a significant reduction in non-radiative recombination and improved charge transport efficiency in the cells treated with 4-IEA, contributing to the overall improved performance of the solar cells.

Munkhtuul Gantumur et al 2024 Jpn. J. Appl. Phys. 63 015501

DOI 10.35848/1347-4065/ad1142

The study in "Japanese Journal of Applied Physics" by Munkhtuul Gantumur et al. explores the use of vacuum-deposited PbI2 to enhance the quality of perovskite films in solar cells. This method significantly improves the film's quality compared to spin-coated PbI2, leading to higher power conversion efficiency and better thermal stability in perovskite solar cells. Vacuum-deposited PbI2 results in uniform, pinhole-free films, facilitating efficient intercalation of MAI and the formation of high-quality MAPbI3 perovskite layers. This method also reduces ion migration, contributing to the improved performance and stability of the solar cells.

How Paios was used

Paios was used for electrochemical impedance spectroscopy (EIS) to examine the perovskite solar cells (PSCs). This technique provided insights into the electrical properties of the cells, such as resistance and capacitance, which are crucial for understanding and improving their performance.

Elkhouly, K., Goldberg, I., Zhang, X. et al.

Nat. Photon. (2024).

https://doi.org/10.1038/s41566-023-01341-7

Imec's research, published in Nature Photonics, details the creation of a perovskite LED stack that dramatically outshines conventional OLEDs.

The team used Setfos to analyze and optimize the light interactions within the perovskite structure. This approach significantly enhanced the LED's brightness and efficiency. The breakthrough paves the way for high-intensity, thin-film perovskite lasers with potential applications in medical diagnostics, environmental sensing, and advanced imaging, heralding a new era in optoelectronic devices. Setfos was instrumental in achieving the precise architecture needed for this revolutionary leap in light-emitting technology.

M. P. A. Nanayakkara, Q. He, A. Ruseckas, A. Karalasingam, L. Matjacic, M. G. Masteghin, L. Basiricò, I. Fratelli, A. Ciavatti, R. C. Kilbride, S. Jenatsch, A. J. Parnell, B. Fraboni, A. Nisbet, M. Heeney, K. D. G. I. Jayawardena, S. R. P. Silva, Adv. Sci. 2023, 10, 2304261. https://doi.org/10.1002/advs.202304261

his paper focuses on the development of tissue-equivalent organic X-ray detectors using high atomic number polythiophene analogues, achieving high sensitivity and flexibility.

How Paios was used

Paios was used to analyze charge transport processes, providing insights into the mobility-lifetime product of the materials, crucial for understanding and improving the performance of the X-ray detectors.

Md. Abdul Karim, Kiyoto Matsuishi, Md. Emrul Kayesh, Yulu He, and Ashraful Islam

ACS Applied Materials & Interfaces 2023 15 (39), 45823-45833

DOI: 10.1021/acsami.3c07903

This paper discusses the improvement of FASnI3 perovskite solar cells' reproducibility and stability by incorporating 4F-PHCl, a reductive molecule, in the perovskite precursor solution. 4F-PHCl enhances the solution's stability, prevents Sn2+ oxidation, and improves the films' crystallinity and stoichiometry, resulting in a power conversion efficiency of 10.86%.

How Paios was used

PAIOS was used to measure transient photovoltage and photocurrent decays, shedding light on charge carrier dynamics and demonstrating improved charge transport and reduced recombination in 4F-PHCl-treated devices.

Xin Zhang, Stijn Eurelings, Andrea Bracesco, Wenya Song, Stijn Lenaers, Wouter Van Gompel, Anurag Krishna, Tom Aernouts, Laurence Lutsen, Dirk Vanderzande, Mariadriana Creatore, Yiqiang Zhan, Yinghuan Kuang, and Jef Poortmans

ACS Applied Materials & Interfaces 2023 15 (40), 46803-46811

DOI: 10.1021/acsami.3c08119

This paper investigates enhancing perovskite solar cells' efficiency and stability using bi-TPAI surface modulation. It significantly improves power conversion efficiency and operational stability by passivating surface defects and facilitating charge extraction.

How Paios was used

Paios was employed for transient photocurrent and photovoltage measurements, revealing optimized charge dynamics and reduced recombination, which contribute to the observed performance improvements.

Zhaoheng Ling, Mohamad Insan Nugraha, Wisnu Tantyo Hadmojo, Yuanbao Lin, Sang Young Jeong, Emre Yengel, Hendrik Faber, Hua Tang, Frédéric Laquai, Abdul-Hamid Emwas, Xiaoming Chang, Temur Maksudov, Murali Gedda, Han Young Woo, Iain McCulloch, Martin Heeney, Leonidas Tsetseris, and Thomas D. Anthopoulos

ACS Energy Letters 2023 8 (10), 4104-4112

DOI: 10.1021/acsenergylett.3c01254

This study explores the use of ethyl viologen (EV) and methyl viologen (MV) as n-type dopants in organic photovoltaics (OPVs). Incorporating these dopants into a ternary blend significantly improves OPV performance, with PCEs up to 19.03%. EV and MV enhance microstructure and absorption, balance carrier mobility, and reduce recombination, offering a promising route for advanced OPV efficiency.

How Paios Was used

In the study, Paios from Fluxim was employed for various measurements in both steady-state and transient modes. Specifically, it was used for Transient Photo-Voltage (TPV) measurements to observe photovoltage decay under small optical perturbations and various light-intensity biases. This helped in analyzing bimolecular charge carrier recombination. Additionally, Photo-CELIV measurements and Electrochemical Impedance Spectroscopy (EIS) were conducted using PAIOS, the latter under an open circuit voltage in the dark across a frequency range of 3 MHz to 300 Hz​

H. Bi, J. Liu, Z. Zhang, L. Wang, G. Kapil, Y. Wei, A. Kumar Baranwal, S. Razey Sahamir, Y. Sanehira, D. Wang, Y. Yang, T. Kitamura, R. Beresneviciute, S. Grigalevicius, Q. Shen, S. Hayase, Adv. Sci. 2023, 10, 2304790. https://doi.org/10.1002/advs.202304790

This paper investigates enhancing the efficiency and stability of MA-free perovskite solar cells using a ferrocene derivative (DBzFe) additive. The additive improves film quality, passivates defects, and inhibits ion migration, achieving a high power conversion efficiency of 23.53%.

How Paios was used

Paios was utilized for Mott-Schottky analysis and temperature-dependent c-f curves, providing insights into charge carrier dynamics, energy barriers for ion migration, and the benefits of DBzFe in improving device performance and stability.

G. Yu, Y. Huang, D. Khan, Y. Sui, S. Wang, X. Yang, W. Zhou, K. Chang, J. Tang, W. Chen, P. Han, Z. Tang, Small 2023, 2307219. https://doi.org/10.1002/smll.202307219

The paper explores the impact of embedding RbPbI3 seeds in PbI2 substrates to tailor the facet orientation and crystallization kinetics of perovskites, improving the performance and durability of perovskite solar cells.

How Paios was used

Paios was used for electrochemical impedance spectroscopy, revealing enhanced carrier dynamics and reduced non-radiative recombination in seed-processed films, contributing to the cells' high efficiency and long-term stability.

Wolfe, K. M.; Alam, S.; German, E.; Alduayji, F. N.; Alqurashi, M.; Laquai, F.; Welch, G. C. Beilstein J. Org. Chem. 2023, 19, 1620–1629. doi:10.3762/bjoc.19.119

The paper focuses on developing and implementing new cathode interlayer (CIL) materials based on N-annulated perylene diimides in organic photovoltaic devices, aiming for efficient and environmentally friendly solar cells.

How was Paios used

PAIOS was used to measure transient photocurrent and light intensity-dependent IV measurements, confirming efficient charge extraction and minimal recombination within the device, contributing to the understanding and optimization of these new CIL materials for improved solar cell performance.

Sasiphapa Rodbuntum, Nuttaya Sukgorn, Narong Chanlek, Hideki Nakajima, Nopporn Rujisamphan, Pipat Ruankham, Duangmanee Wongratanaphisan, Anusit Kaewprajak, and Pisist Kumnorkaew

ACS Applied Energy Materials 2023 6 (20), 10364-10375

DOI: 10.1021/acsaem.3c01184

The paper addresses enhancing perovskite solar cells' performance and stability using a dual interfacial tin-oxide layer with chloride salt. It achieved a high power conversion efficiency and remarkable operational stability over 2400 hours.

How Paios was used

Paios was utilized for electrical and optical characterization, particularly for electrical impedance spectroscopy and intensity-modulated photocurrent spectroscopy measurements, providing insights into charge transport and recombination dynamics at the device interfaces.

Li, Z., Chen, Z., Shi, Z. et al. Nat Commun 14, 6441 (2023). https://doi.org/10.1038/s41467-023-41929-9

This paper focuses on enhancing the performance and response speed of perovskite light-emitting diodes (PeLEDs) by engineering the charge injection at the organic-inorganic heterointerfaces. They introduced a self-assembled monolayer to improve interface robustness, passivate interfacial traps, and align energy levels.

How Paios was used

Paios was used to study the transient photo-voltage and photocurrent responses, revealing improved charge injection and transport properties, which significantly enhanced the device's efficiency and response speed.

J. Chen, G. Zhang, Z. Chen, J. Xiao, T. Xia, X. Li, H.-L. Yip, Small 2023, 2306471.

https://doi.org/10.1002/smll.202306471

The study enhances organic solar cells' performance and photostability by incorporating a fluorescent conversion agent, CBS, into the ZnO electron-transporting layer. This innovative hybrid ETL boosts power conversion efficiencies and shields active layers from UV-induced degradation.

How Paios was used

Paios was employed to measure transient photocurrents, illuminating the charge extraction process and demonstrating improved charge transport and reduced recombination in devices with the ZnO:CBS ETL.

S. Tang, J. M. dos Santos, J. Ràfols-Ribé, J. Wang, E. Zysman-Colman, L. Edman, Adv. Funct. Mater. 2023, 33, 2306170. https://doi.org/10.1002/adfm.202306170

The paper introduces MR-TADF emitters into light-emitting electrochemical cells (LECs) for narrowband and efficient emission. It demonstrates a metal-free MR-TADF LEC delivering blue light with a narrow full-width-at-half-maximum (FWHM) of 31 nm, a high external quantum efficiency of 3.8%, and significant electrochemical doping capacity.

How Setfos was used

Setfos was used to perform optical simulations, helping to understand and optimize the emission and efficiency of the device by simulating the position of emissive dipoles within the active material.

Zhang, T., Zhao, F., Liu, P., Tan, Y., Xiao, X., Wang, Z., Wang, W., Wu, D., Sun, X.W., Hao, J., Xing, G. and Wang, K. (2023)

Adv. Photonics Res., 4: 2300146.

https://doi.org/10.1002/adpr.202300146

The paper investigates electron leakage in green InP Quantum-Dot Light-Emitting Diodes (QLEDs), causing carrier imbalance and reduced efficiency. It identifies the Fermi energy difference between green InP/ZnS Quantum Dots and the ITO anode as the main cause.

How Setfos was used

Setfos was used for electrical simulations of recombination rates, helping to understand electron leakage paths and the impact of an ultrathin LiF layer, which ultimately improves device performance by enhancing electron confinement and hole injection.

S. Alam, H. Aldosari, C. E. Petoukhoff, T. Váry, W. Althobaiti, M. Alqurashi, H. Tang, J. I. Khan, V. Nádaždy, P. Müller-Buschbaum, G. C. Welch, F. Laquai

Adv. Funct. Mater. 2023, 2308076. https://doi.org/10.1002/adfm.202308076

This paper investigates the impact of thermal annealing on PM6:Y6-based organic solar cells, focusing on performance degradation due to structural and morphological changes at elevated temperatures. It finds that VOC and FF significantly decrease with annealing above 140°C due to altered charge transport and extraction.

How Setfos was used

Using SETFOS software, the study simulates device performance, correlating optical-electrical properties with device parameters to understand the degradation mechanisms and guide future improvements.

How Paios was used

Paios was used to measure transient photocurrent, photo-voltage, and charge extraction properties, providing insights into charge generation, recombination, and extraction mechanisms, helping to understand the performance drop at elevated annealing temperatures.

S. Sasaki, K. Goushi, M. Mamada, S. Miyazaki, K. Miyata, K. Onda, C. Adach Adv. Optical Mater. 2023, 2301924. https://doi.org/10.1002/adom.202301924

The paper explores intramolecular triplet–triplet annihilation (TTU) upconversion in organic light-emitting diodes (OLEDs) for enhanced electroluminescence efficiency. The study focuses on the intramolecular TTU of anthracene dimers in OLEDs, showing improved electroluminescence efficiency under low dopant concentrations.

How Setfos was used

Setfos was utilized to estimate the out-coupling efficiency of the OLEDs, contributing to the understanding of the TTU process and device optimization.

Q. Wang, H. Zhu, Y. Tan, J. Hao, T. Ye, H. Tang, Z. Wang, J. Ma, J. Sun, T. Zhang, F. Zheng, W. Zhang, H. W. Choi, W. C. H. Choy, D. Wu, X. W. Sun, K. Wang. Adv. Mater. 2023, 2305604.

https://doi.org/10.1002/adma.202305604

The paper demonstrates a spin quantum dot light-emitting diode (spin-QLED) using 2D chiral perovskite as a spin injection layer based on the chiral-induced spin selectivity (CISS) effect, enabling spin-dependent carrier transport. It operates at room temperature and zero magnetic field, achieving circularly polarized electroluminescence (CP-EL) with an asymmetric factor of 1.6 × 10^-2. The work highlights the potential of chiral materials in spintronics and quantum-based devices.

How Setfos was used

Setfos simulation was used to analyze the recombination center and carrier recombination rate distribution in the device, providing insights into the performance and guiding future improvements.

Darshan H. Parmar, Benjamin Rehl, Ozan Atan, Sjoerd Hoogland, and Edward H. Sargent

ACS Applied Materials & Interfaces Article ASAP

DOI: 10.1021/acsami.3c14611

Colloidal quantum dot photodetectors exceed silicon's limits by detecting longer wavelengths, with performance depending on the ligand concentration during processing. This study connects simulated and actual photocurrent responses, showing that different ligand concentrations uniquely impact trap state density and device behavior.

How Setfos was used

Setfos was used to show how the transient measurements were consistent with a changing trap density in the photodetector active layer with respect to ligand exchange concentration.

Qi Dong, Liping Zhu, Shichen Yin, Lei Lei, Kenan Gundogdu, and Franky So

ACS Photonics 2023 10 (9), 3342-3349

DOI: 10.1021/acsphotonics.3c00812

Researchers have developed a highly efficient linearly polarized organic LED, capitalizing on the inherent polarization properties of the transverse electric waveguide mode within the device. Utilizing a linear grating, they achieved 67.6% light confinement in this mode, resulting in a polarized LED with a current efficiency of 136 cd/A and a polarization ratio exceeding 30. Further enhancements to current efficiency are possible, making this architecture adaptable for various thin-film LED applications in photonics.

How Setfos was used

The researchers used Setfos for optical simulations to analyze the spatial distribution of different modes in the top-emitting OLED device, determine the optimized device geometry, and simulate the dissipated power versus the effective refractive index in the optimized condition to enhance the efficiency of polarized emission.

Bandgap Tunable Perovskite for Si-Based Triple Junction Tandem Solar Cell: Numerical Analysis-Aided Experimental Investigation

Jia-Ci Jhou, Ashish Gaurav, Hsin-Ting Lin, and Ching-Fuh Lin

ACS Applied Energy Materials 2023 6 (18), 9434-9445

DOI: 10.1021/acsaem.3c01344

Researchers developed a new technique to fabricate perovskite absorbing layers for multijunction solar cells, achieving a record power conversion efficiency of 26.4%. This technique involves a double-sided sandwich evaporation process that allows for precise control over the halide ratio and B-site doping of the perovskite absorber layers. The resulting triple-junction tandem solar cell exhibits significantly higher efficiency than previous designs.

How Setfos was used.

theoretical insight for the optimal perovskite thickness was gained using Setfos by taking into account the reflection of the bottom cell, so the thickness of the top layers could be reduced.

Warby, J., Shah, S., Thiesbrummel, J., Gutierrez-Partida, E., Lai, H., Alebachew, B., Grischek, M., Yang, F., Lang, F., Albrecht, S., Fu, F., Neher, D., Stolterfoht, M.,

Adv. Energy Mater. 2023, 2303135.

https://doi.org/10.1002/aenm.202303135

This research addresses the discrepancy between open-circuit voltages (VOC) and internal voltages in perovskite solar cells, often attributed to non-radiative recombination losses. The study extends classical theories from silicon solar cells to explain the mismatch through partial resistances/conductivities of carrier types. It also reveals how mobile ions in perovskite cells contribute to this mismatch, explaining phenomena like light soaking and aging-induced VOC losses. These insights offer new perspectives on degradation issues and guide principles for optimizing VOC to enhance perovskite solar cell performance.

How Setfos was used

Band diagram simulation of perovskite cells with ions

Rohit D. Chavan, Bartłomiej Bończak, Joanna Kruszyńska, Apurba Mahapatra, Muhammad Ans, Jan Nawrocki, Kostiantyn Nikiforow, Pankaj Yadav, Jan Paczesny, Faranak Sadegh, Muhittin Unal, Seckin Akin, and Daniel Prochowicz

Chemistry of Materials 2023 35 (19), 8309-8320

DOI: 10.1021/acs.chemmater.3c01995

This study introduces a novel azahomofullerene (AHF-4) as an interlayer in perovskite solar cells (PSCs), enhancing charge transfer and film quality while reducing recombination. AHF-4 outperforms the standard fullerene derivative PCBM, achieving higher efficiency (21.43%) and better stability under light and heat, promising advancements in PSC performance and durability.

How Litos Lite and Litos were used

The photovoltaic performance was evaluated using a Fluxim Litos Lite setup, equipped with a Wavelabs Sinus LS2 solar simulator with AM 1.5 spectrum for excitation.

Aging tests were also performed using a Fluxim Litos setup, and 1 Sun equivalent illumination with no UV component, holding the substrates at 45 ± 5 °C in a N2 atmosphere and using an MPP tracking algorithm.

Moritz C. Schmidt, Emilio Gutierrez-Partida, Martin Stolterfoht, and Bruno Ehrler

PRX Energy 2, 043011 – Published 13 November 2023

https://doi.org/10.1103/PRXEnergy.2.043011

This study reveals that analyzing capacitance transients in perovskite solar cells is more complex than previously thought. It demonstrates that the direction of these transients is influenced by the cell's layer dominating capacitance modulation, not by the polarity of migrating species. This highlights the significant role of transport layers in characterizing mobile ions in perovskites.

Setfos was used

To investigate the role of the polarity of mobile ions in capacitance measurements the researchers simulated the behavior of the capacitance as a function of time after a voltage pulse. The Drift-Diffusion module in Setfos was used to simulate the capacitance transients.

Binh Minh Nguyen, Markus Schmid, Johann Kirsch, Albin Cakaj, and Wolfgang Brütting

Chemistry of Materials 2023 35 (17), 7333-7343

DOI: 10.1021/acs.chemmater.3c01804

The research explores how four nonpolar dyes orient within neat films and doped guest-host systems in organic light-emitting diodes (OLEDs). It identifies shape anisotropy and the relationship between the substrate temperature during deposition and the system's glass transition temperature (Tg) as critical to the alignment of emissive transition dipoles. Notably, in mixed cohost systems with components of differing Tgs, the alignment may not align with the mixed host's effective Tg. The study also proposes using a molecule's principal moments of inertia to assess its reorientation resilience and aspect ratio to gauge shape anisotropy.

How Phelos was used

Angular-Dependent Photoluminescence measurements were performed with Phelos.

Hye In Yang, Nagarjuna Naik Mude, Jin Young Kim, Jun Hyeog Oh, Ramchandra Pode, and Jang Hyuk Kwon,

Opt. Express 31, 18407-18419 (2023)

https://doi.org/10.1364/OE.487301

The study presents an enhanced top emission OLED (TEOLED) device structure that significantly improves light extraction, specifically by addressing waveguide mode loss in the thin film encapsulation (TFE) layer. By introducing a low refractive index (RI) layer between the capping layer (CPL) and the aluminum oxide (Al2O3) layer, the device manipulates evanescent waves to redirect trapped light within the device, increasing its extraction. This novel TFE structure (CPL/low RI layer/Al2O3/polymer/Al2O3) led to a 23% increase in current efficiency and a 26% enhancement in the blue index value for the blue TEOLED device. This method shows significant potential for advancing flexible optoelectronic device encapsulation technologies.

How Setfos was used

SETFOS 5.1 is used as an optical simulator. The RI of the glass substrate, indium tin oxide (ITO), and organic layers are taken as ∼1.5, 1.8∼2.0, and ∼1.8, respectively. The RI and extinction coefficient of silver (Ag) and magnesium (Mg):Ag (10:1) used as an anode and cathode, respectively, are taken from the reported values. For the EML, the thin film photoluminescence spectrum of 2,12-di-tert-butyl-N,N,5,9-tetrakis(4-(tert-butyl)phenyl)-5,9-dihydro-5,9-diaza-13bboranaphtho[ 3,2,1-de]anthracen-7-amine (DABNA-NP-TB) for the blue TEOLED device, bis[2- (2-pyridinyl-N)phenyl-C](acetylacetonato)iridium(III) for the green TEOLED device, and (bis(4- methyl-2-(3,5-dimethylphenyl)quinoline))Ir(III (tetramethylheptadionate) for the red TEOLED device are used.

Dian Luo, Wei-Yu Chen, Wei-Lun Syu, Shun-Wei Liu, and Chih-Hao Chang

ACS Photonics 2023 10 (8), 2874-2885

DOI: 10.1021/acsphotonics.3c00590

The study introduces four innovative design strategies for tandem organic light-emitting diodes (TOLEDs) to overcome the efficiency loss caused by charge-generation layer (CGL) interactions in multi-layer devices. The designs include an optimized CGL, an exciplex host in the emitting layer for improved carrier balance and reduced voltage, simplified architecture, and nanoparticle diffusers. These led to a three-stacked TOLED reaching 78.7% efficiency, 2.5 times higher than conventional devices. Adding a nanoparticle diffuser further increased efficiency to 123.9%, with a record luminance of 411,531 cd/m². The findings show promise for TOLEDs in OLED phototherapy and display applications with high efficiency and luminance.

How Setfos was used

Setfoswas chosen as the calculation tool for the external optical coupling of the devices.

Luo, D., Hou, M.-C., Wang, K.-Y., Chang, C.-H., Liu, S.-W., Lu, C.-W. and Su, H.-C. (2023),

Adv. Mater. Technol., 8: 2300563. https://doi.org/10.1002/admt.202300563

The research presents a tandem white OLED/LEC hybrid device, combining a red OLED and a blue LEC, which simplifies fabrication compared to multi-layered OLEDs. The device includes a charge-generating layer (CGL) that not only links the two, but also improves carrier balance, leading to an external quantum efficiency (EQE) of 21.53%. Efficiency jumps to 37.88% when using a diffusive substrate. This demonstrates a simpler yet highly efficient structure, offering promising potential for cost-effective lighting solutions.

How Setfos was used

To clarify the relationship between the recombination zone position and the optical mode distribution for Device B, Device R, and Device T. The optical simulation software Setfos was employed as the analysis tool as was the optical mode distribution of the devices.

Huseynova, G., Ràfols-Ribé, J., Auroux, E. et al. Sci Rep 13, 11457 (2023).

https://doi.org/10.1038/s41598-023-38006-y

The performance of light-emitting electrochemical cells (LECs) is greatly influenced by the position of the emissive p–n junction within the device. A new "chemical pre-doping" method that incorporates a reductant into the active material ink shifts the p–n junction closer to the anode, which enhances emission efficiency and device stability. This approach offers a practical solution for optimizing the spatial configuration of p–n junctions in LECs.

How Setfos was used

The optical simulations were carried out with Setfos. The position of the emissive p–n junction within the active material was determined by minimizing the root mean square error between the simulated and the measured angle-dependent EL data.

The exciton formation rate profile in the interelectrode gap was determined with the drift–diffusion module of the same software, and the simulated three-layer device featured an ITO anode (thickness = 145 nm), an active material (thickness = 150 nm), and an Al cathode.

Yan-Yun Jing et al. ,Sci.Adv.9, eadh8296(2023). DOI:10.1126/sciadv.adh8296

Here the researchers have developed a new strategy to create red Multiple Resonance (MR) emitters for OLEDs achieves high efficiency and color purity by adjusting the π-conjugation and electron-donating properties within a boron-based structure. The result is a range of emissions with narrow bandwidths and a particularly pure-red device meeting the BT.2020 standard with high quantum efficiency and brightness. This approach suggests a promising direction for developing OLED materials with superior color performance.

How Setfos was used

The experimental EQEs closely aligned with the theoretical efficiencies predicted by optical simulations using Setfos software (33.6% for CzIDBNO and 27.9% for IDIDBNO), which further demonstrated the intricate interplay of these parameters on outcoupling efficiency and overall device performance.

Yu Zhang, Weiqing Nie, Mengli Hu, Wu Liu, Heng Liu, Xiaomin Huo, Yao Lu, Dandan Song, Bo Qiao, Zhiqin Liang, Zhiqiang Jiao, Zheng Xu, Guangcai Yuan, and Suling Zhao

ACS Photonics 2023 10 (10), 3521-3530

https://doi.org/10.1021/acsphotonics.3c00524

This research outlines the advancement in tandem optoelectronic devices, specifically a perovskite/organic quasi-tandem system for narrowband photodetectors (NPDs) targeting the visible to near-infrared spectrum. By varying the composition of perovskite and organic layers, the spectral response is tunable, enhancing device selectivity and flexibility. Achieving a peak response near 790 nm with a 41 nm bandwidth, these NPDs exhibit rapid submicrosecond response times, significantly outperforming traditional thick-layer photodetectors, marking a step forward in the development of ultra-fast NPDs.

How Setfos was used

Setfos was utilized to stimulate the penetration of different monochromatic light, the thickness of perovskite (MAPbI3) was set as 1700 nm, and a 150 nm of organic blend layer (PM6:IT-4F) was set on the perovskite. Take thickness as the scanning parameter, with a step size of 10 nm. The optical parameters (n, k) of the materials are obtained through an ellipsometer.

Noel C. Giebink and Stephen R. Forrest

Phys. Rev. Lett. 130, 267002 – Published 29 June 2023

https://doi.org/10.1103/PhysRevLett.130.267002

The study establishes a thermodynamic limit for OLED efficiency, revealing that OLEDs require higher voltage for the same brightness compared to inorganic LEDs due to strong exciton binding. Optimizing factors like low exciton binding energy, long exciton lifetime, and efficient electron-hole recombination can minimize OLED overpotential, suggesting top-performing OLEDs may be near their efficiency limit. This framework aids in developing low-voltage OLEDs for displays and lighting.

How Setfos was used

Setfos was used to validate the theoretical model considering also exciton dissociation.

Juhui Oh, Ju-Hyeon Kim, Yong Ryun Kim, Ardalan Armin, Sanseong Lee, Kiyoung Park, Hongkyu Kang, and Kwanghee Lee

ACS Applied Materials & Interfaces 2023 15 (36), 42802-42810

https://doi.org/10.1021/acsami.3c08028

This research discusses the challenge of balancing transparency and efficiency in transparent organic solar cells (T-OSCs) for smart solar windows. A new tungsten oxide (WO3)-based multilayer top electrode is presented that achieves both high photopic transmittance (46.7%) and power conversion efficiency (7.0%), with superior light utilization and thermal stability. This development offers new directions for creating efficient, transparent solar cells for energy-harvesting windows.

How Setfos was usedSetfos

To predict the transparent OSC performance, optical simulation was conducted with the commercial software Setfos using n and k values obtained from ellipsometry.

Jinno, H., Shivarudraiah, S. B., Asbjörn, R., Vagli, G., Marcato, T., Eickemeyer, F. T., Pfeifer, L., Yokota, T., Someya, T., Shih, C.-J.,

. Adv. Mater. 2023, 2304604.

https://doi.org/10.1002/adma.202304604

This research presents a breakthrough in ultrathin, flexible skin optoelectronics for Internet of Things (IoT) applications. Traditional issues like underperformance due to low polymer process temperatures and spectral distortion from bending are overcome using solution-processed perovskite semiconductors. The study introduces high-efficiency perovskite solar cells and LEDs on polymer films with exceptional thermal stability, achieving record efficiencies (18.2% for solar cells, 15.2 cd A−1 for LEDs) and bending-resistant light emission. This advancement enables reliable, high-performance, self-powered wearables and IoT sensors, demonstrating practical applications such as accurate pulse monitoring at a high selectivity rate.

How Setfos Was used

Finite element analysis for ultraflexible LED was simulated with the Setfos emission module. By expecting the dipole emission model of LED, the module allows to deliver emission spectra of ultraflexible LED with different angle.

Kang, H., Hwang, Y., Kang, Cm. et al.

Sci Rep 13, 14070 (2023).

https://doi.org/10.1038/s41598-023-41033-4

This research explores electrical crosstalk in high-resolution OLED microdisplays impacting color distortion, especially in AR/VR applications. Through simulations and experimental measures, it was found that decreasing sheet resistance in the common organic layer elevated crosstalk, and increasing pixel density led to a color gamut reduction.

How Laoss Simulation was used

Simulation process. Commercial software LAOSS (Fluxim) which used 2 + 1D finite element model based on the conductivity of the common layer17,18 and J–V–L characteristics of the fabricated white OLED were used for the electrical crosstalk calculation.

Dr. Camilla Arietta VAEL-GARN

Ph. D Thesis, EPFL , 12 Sept. 2023

https://doi.org/10.5075/epfl-thesis-10350

The study explores polymeric semiconductors in organic electronics, using drift-diffusion simulation to study three areas. First, the applicability of thermally stimulated current measurement for studying trap states in organic semiconductors is investigated, identifying a reliable formula for data analysis. Second, reversible trap states in a polymeric light-emitting diode are studied, suggesting trap state formation and disaggregation may involve water and oxygen molecules. Lastly, the operational principles of an upconverter device converting near infra-red to visible light are examined, finding that electron mobility in the emission layer significantly affects the device's response time.

Han Bin Cho, Ju Yeon Han, Ha Jun Kim, Noolu Srinivasa Manikanta Viswanath, Yong Min Park, Jeong Wan Min, Sung Woo Jang, Heesun Yang, and Won Bin Im

ACS Appl. Mater. Interfaces 2023, 15, 24, 29259–29266, June 8, 2023

https://doi.org/10.1021/acsami.3c02857

Quantum dot light-emitting diodes (QLEDs) often use PEDOT:PSS as a hole injection layer (HIL), but it has a high energy barrier for hole injection, resulting in low efficiency. Researchers improved device efficiency by using a bilayer HIL with VO2 and PEDOT:PSS, achieving an 18% external quantum efficiency, 78 cd/A current efficiency, and 25,771 cd/m² maximum luminance, compared to 13%, 54 cd/A, and 14,817 cd/m² for the PEDOT:PSS-based QLED. This approach effectively reduced the energy barrier between indium tin oxide (ITO) and PEDOT:PSS, boosting QLED efficiency.

How Setfos was used

The optical simulation was conducted using the advanced simulation software Setfos.

Sarmad Feroze, Andreas Distler, Karen Forberich, Iftikhar Ahmed Channa, Bernd Doll, Christoph J. Brabec, Hans-Joachim Egelhaaf,

Solar Energy, Volume 263, 2023, 111894, ISSN 0038-092X,

https://doi.org/10.1016/j.solener.2023.111894

The 2022 global PV installations accounted for 5% of electricity consumption. To reach 2 TWP annually by 2030, leveraging existing urban surfaces is vital. BAPV/BIPV transform buildings into energy producers. Currently dominated by silicon PV modules, the market has underutilized Organic Photovoltaics (OPV), a cost-effective, customizable, and flexible alternative for BIPV applications. This study analyzes OPV's outdoor performance compared to monocrystalline silicon modules, aiming to provide insights for forecasting the annual energy yield of building-integrated OPV modules, advancing OPV technology for BIPV applications.

How Setfos was used

Setfos software by Fluxim AG was used for optical simulations to evaluate absorption in the active layer of the OPV device.

Zhang, Z., Wang, L., Bi, H., Baranwal, A. K., Kapil, G., Sanehira, Y., Liu, J., Liu, D., Shen, Q., Hayase, S.,

Adv. Optical Mater. 2023, 2300962.

https://doi.org/10.1002/adom.202300962

To enhance the efficiency of tin halide perovskite solar cells (PKSCs), researchers addressed defects like Sn4+ and iodide vacancies by introducing copper iodide (CuI) doping. A preprocessing method for CuI improved perovskite layer quality, resulting in efficiency increases from 9.8% to 13.1% for P-I-N structures and 9.4% to 10.5% for hole transport layer (HTL)-free structures. These doped tin-PKSCs also exhibited improved stability, retaining 75% of their initial power conversion efficiency after 102 days of storage.

How Paios was used

Intensity-modulated photovoltage spectroscopy (IMVS), Intensity-modulated photovoltage spectroscopy (IMPS), Transient photovoltaic voltage (TPV), and Transient photovoltaic current (TPC) were carried out via PAIOS software.

Lin-jie Yang, Wenye Xuan, David Webster, Lethy Krishnan Jagadamma, Teng Li, David N. Miller, David B. Cordes, Alexandra M. Z. Slawin, Graham A. Turnbull, Ifor D. W. Samuel, Hsin-Yi Tiffany Chen, Philip Lightfoot, Matthew S. Dyer, and Julia L. Payne

Chemistry of Materials 2023 35 (10), 3801-3814

DOI: 10.1021/acs.chemmater.2c03125

This study demonstrates the tunability of organic-inorganic metal halides through anion substitution, incorporating bromine into [H3N(CH2)6NH3]PbBr4 to create [H3N(CH2)6NH3]PbBr4·Br2. This inclusion of molecular bromine leads to a reduced band gap, structural phase transition, and improved carrier mobility. The key to this manipulation is the formation of halogen bonds between Br2 and Br in the [PbBr4]∞ layers. This work opens possibilities for tuning electronic properties in layered organic-inorganic perovskites and represents the first example of molecular bromine inclusion in such a material.

How Paios was used

The current−voltage measurements were carried out using the all-in-one characterization platform Paios, Fluxim AG, Switzerland. The voltage scan range used was 0−9 V.

J. H. Siew, Y. -H. Chen, Y. -L. Chang, C. -H. Lai and T. -Y. Lin,

IEEE Journal of Photovoltaics, vol. 13, no. 4, pp. 503-509, July 2023,

doi: 10.1109/JPHOTOV.2023.3271891.

Researchers investigated a low-temperature heat-soaking (HS) treatment to mitigate the rollover effect in copper indium gallium sulfur selenide (CIGSSe) solar cells. Excessive sulfur accumulation on the absorber's backside forms a Schottky barrier, causing current-voltage rollover. HS treatment reduced saturation and improved cell efficiency by over 6%. Elemental redistribution after HS reduced sulfur accumulation, enabling Fowler-Nordheim tunneling through a shortened Schottky barrier width. This study offers a simple, practical strategy to address the second reverse diode effect caused by sulfurization in CIGSSe solar cells.

How Paios was used

Temperature-dependent dark current density and voltage were measured using a Paios system with Fluxim Characterization Suite software attached to a temperature-controlled probe stage.

Abu Bakar Siddik, Epimitheas Georgitzikis, Yannick Hermans, Jubin Kang, Joo Hyoung Kim, Vladimir Pejovic, Itai Lieberman, Pawel E. Malinowski, Andriy Kadashchuk, Jan Genoe, Thierry Conard, David Cheyns, and Paul Heremans

ACS Applied Materials & Interfaces 2023 15 (25), 30534-30542

DOI: 10.1021/acsami.3c03708

This study presents a high-speed, low dark current near-infrared organic photodetector (NIR OPD) on a silicon substrate using amorphous indium gallium zinc oxide (a-IGZO) as the electron transport layer (ETL). Detailed characterization reveals the dark current mechanism as trap-assisted field-enhanced thermal emission, significantly reduced by introducing an interfacial layer. The NIR OPD achieves a low dark current of 125 pA/cm² at -1 V reverse bias and boasts a rapid photo response time, making it suitable for high-quality sample image capture in an imager on a complementary metal oxide semiconductor read-out circuit.

How Paios was used

Q-DLTS and TPV decay measurements were performed using Paios.

Mohammed Sahal, Jie Molloy, Venkateshwaran Ravi Narayanan, Leila Ladani, Xiaochuan Lu, and Nicholas Rolston

ACS Omega 2023 8 (31), 28651-28662

DOI: 10.1021/acsomega.3c03114

Researchers have developed a high-throughput, one-minute process for printable thin-film ceramic solid-state electrolytes (SSEs) called "Robust LLTO" (R-LLTO). R-LLTO exhibits excellent mechanical properties, with flexibility, low modulus (~35 GPa), and high fracture toughness (>2.0 MPa m). This opens new design possibilities for robust solid-state batteries with improved energy density and processability compared to traditional SSEs.

How Paios was used

The complex impedance response of the inplane configuration was measured using a Paios measurement system (Fluxim AG) by varying the frequency from 10 Hz to 10 MHz for an applied voltage with an amplitude of 50 mV. Data from EIS measurements were fitted with simulated response of equivalent circuits using Fluxim’s Characterization Suite software.

Zhou, X., Yan, Y., Zhang, F. et al.

J Mater Sci: Mater Electron 34, 1415 (2023).

https://doi.org/10.1007/s10854-023-10838-4

To enhance the performance and stability of organic solar cells (OSCs), a binary anode buffer layer strategy was employed using molybdenum oxide (MoO3) and PEDOT:PSS. This improved work function and interface contact, increasing the power conversion efficiency (PCE) from 16.25% to 17.34%. Additionally, MoO3 prevented direct contact between PEDOT:PSS and ITO, enhancing device stability. This approach offers a simple and efficient method for high-efficiency, stable OSCs suitable for commercial applications.

Andre Müller, Faruk Okur,ab Abdessalem Aribia, Nicolas Osenciat, Carlos A. F. Vaz, Valerie Siller, Mario El Kazzi, Evgeniia Gilshtein, Moritz H. Futscher, Kostiantyn V. Kravchyk, Maksym V. Kovalenko and Yaroslav E. Romanyuk

Mater. Adv., 2023,4, 2138-2146

Integrating Li7La3Zr2O12 (LLZO) solid-state electrolytes with high-energy cathodes in all-solid-state batteries faces challenges due to diffusion and solid-state reactions at the cathode-electrolyte interface during fabrication. This study explores lithiated Nb, Al, and Ti metal oxide interlayers as diffusion barriers to enhance Li-ion transfer between LiCoO2 and LLZO. These interlayers reduce interfacial impedance from 8 kΩ cm² to 1 kΩ cm², improving battery performance. Li-Nb-O interlayer stands out, delivering the highest discharge capacities.

How Paios was used

Electrochemical impedance spectroscopic measurements were performed between 5 MHz and 1 Hz with an AC amplitude of 50 mV using Paios.

Zhu, J., Luo, Y., He, R. et al.

Nat Energy 8, 714–724 (2023).

https://doi.org/10.1038/s41560-023-01274-z

A donor-acceptor molecule, 2F, serves as a hole-selective contact for both wide-bandgap (WBG) and low-bandgap (LBG) perovskite subcells in all-perovskite tandem solar cells. In the WBG cell, 2F extracts holes efficiently and minimizes recombination losses by passivating defects. In the LBG cell, 2F suppresses losses, enhances film quality, and regulates crystal growth. This results in WBG and LBG devices with efficiencies of 19.33% and 23.24%, respectively, contributing to a monolithic all-perovskite tandem solar cell with an efficiency of 27.22%.

How Paios was used

Transient photovoltage (TPV), transient photocurrent (TPC), Mott–Schottky plots and electrochemical impedance spectroscopy were performed using the all-in-one characterization system Paios from Fluxim.

Ma et al.,

solar cells, Chem (2023),

https://doi.org/10.1016/j.chempr.2023.04.021

Polythiophenes, while cost-effective, lag behind in organic solar cells. Researchers studied polythiophene:polymer acceptor (PY-IT) interactions, highlighting the role of electrostatic forces. Introducing electron-withdrawing groups to P3HT reduced intermolecular interactions, improving blend miscibility. This led to a record-high 15.3% power conversion efficiency in PDCBT, advancing polythiophene-based all-polymer solar cells for practical use.

Liu, L., Tang, J., Li, S., Yu, Z., Du, J., Bai, L., Li, X., Yuan, M. and Jiu, T. (2023),

Adv. Funct. Mater., 33: 2303038.

https://doi.org/10.1002/adfm.202303038

To enhance perovskite solar cell (PSC) performance, surface passivation using 2D perovskite is crucial, but random orientation hinders carrier transport. A surface passivation layer with multiple nitrogen sites from the organic spacer molecule PAH is introduced on FAPbI3 perovskite. Through interactions with PbI2, PAH effectively passivates FAPbI3 defects, with 2D nanosheets growing perpendicularly for improved charge transfer. This achieves an impressive 24.6% efficiency and excellent long-term stability, offering insights into designing efficient and stable PSCs with novel organic halide salts.

How Paios was used

The TPC/TPV decays were recorded via all-in-one characterization platform Paios.

Lee, J., Georgitzikis, E., Hermans, Y. et al.

Nat Electron 6, 590–598 (2023).

https://doi.org/10.1038/s41928-023-01016-9

Thin-film image sensors with pinned photodiode structures, using organic or colloidal quantum dot photodiodes, demonstrate noise performance comparable to silicon-based counterparts. These sensors exhibit low noise, reduced dark current, high capacity, and efficient electron-to-voltage conversion. For instance, an organic absorber-based sensor achieves 54% quantum efficiency at 940 nm with 6.1e– read noise.

How Paios was used

The transient photoresponse, photocurrent linearity and capacitance–voltage measurements were performed using a Paios all-in-one system by Fluxim.

Pengyu Su, Huan Bi, Du Ran, Li Liu, Wenjing Hou, Guangzhao Wang, Wenbing Shi,

Chemical Engineering Journal, Volume 472, 2023, 145077, ISSN 1385-8947,

https://doi.org/10.1016/j.cej.2023.145077

In a bid to enhance perovskite solar cell (PSC) performance and stability, a novel interfacial buffer layer called Ethyl p-nitrobenzoate (EPN) was introduced. EPN improved film quality, reduced defect density, relieved interfacial stress, and suppressed nonradiative recombination at the interface. This innovation led to a high 23.16% power conversion efficiency and improved device stability, showcasing the potential of multifunctional interfacial buffer layers in high-performance PSCs.

How Paios was used

TPC, TPV, IMPS, IMVS, and built-in potential were carried out via PAIOS in the structure of ITO/SnO2/(EPN)/perovskite/Spiro-OMeTAD/Ag, and the results were fitted using the companion software of PAIOS.

Irfan Habib, Pascal Kaienburg, Dondong Xia, Olivia Gough, Ming Zhu, Joseph Spruce, Weiwei Li, Moritz Riede;

APL Mater. 1 June 2023; 11 (6): 061128.

https://doi.org/10.1063/5.0148208

The power conversion efficiency of solution-processed organic solar cells (OSCs) nearly doubled when non-fullerene acceptors (NFAs) replaced fullerene derivatives. However, this transition hasn't fully occurred in vacuum-thermal evaporated (VTE) OSCs because most NFAs are too large to evaporate without damage. We've fabricated VTE OSCs using BTIC-H, a smaller NFA, and observed promising results, highlighting the potential for high-performance VTE NFAs in OSCs.

How Paios was used

Open-circuit corrected charge carrier extraction was performed with Paios from Fluxim AG, Switzerland. The 60 nmthick BHJ samples were illuminated with a white LED light for 100 μs until a steady-state Voc was reached. Delay times were varied between a few μs and 1 ms. The linear voltage pulse (ramp rate of 200 and 400 V/ms) was chosen long enough (∼30 μs) such that all mobile carriers were extracted, and the current peak decayed to the displacement current obtained from a dark measurement with no offset voltage applied.

H. Fu, J. Peng, L. Xiang, Q. Zhang, X. Tan and Y. Lei,

IEEE Transactions on Electron Devices, vol. 70, no. 6, pp. 3239-3244, June 2023,

https://ieeexplore.ieee.org/document/10098909

A scalable, low-voltage flexible organic field-effect transistor (OFET) design utilizes blade-deposited thick cross-linked polyvinyl alcohol (c-PVA) dielectric to achieve <1V operation, nearly 10 cm²/V·s mobility, and excellent mechanical stability, making it ideal for cost-effective high-performance, low-voltage flexible OFET manufacturing in organic electronics.

How Paios was used

The capacitance and impedance spectra were recorded by the all-in- one measurement platform Paios.

Yajie Cheng, Junjie Ma, Huaiqing Luo, Meng Cai, Tangyue Xue, Guanghui Yu, Ziqiu Ren, Yanlin Song, Shou Peng, Yiqiang Zhang,

Nano Energy, Volume 115, 2023, 108690, ISSN 2211-2855,

https://doi.org/10.1016/j.nanoen.2023.108690

This study addresses the issue of undesirable segregation of inactive secondary phases in perovskite films, which negatively impacts charge-carrier transport and stability. The research delves into the chemical reactions and structural relationships responsible for this behavior. By converting the photoactive phase into an inactive one, a high-quality perovskite-PbI2 heterojunction film is created, improving carrier dynamics and achieving remarkable light resistance. The resulting perovskite solar cells reach an impressive efficiency of 24.23%. This work offers valuable insights into designing crystal structures for high-quality perovskite heterojunction devices.

How Paios was used

EIS, TPC, TPV, and capacitance-voltage (C-V) measurements were performed by Paios from Fluxim

Huan Bi, Jiaqi Liu, Raminta Beresneviciute, Daiva Tavgeniene, Zheng Zhang, Liang Wang, Gaurav Kapil, Chao Ding, Shahrir Razey Sahamir, Yoshitaka Sanehira, Ajay Kumar Baranwal, Takeshi Kitamura, Dandan Wang, Yuyao Wei, Yongge Yang, Dong-Won Kang, Saulius Grigalevicius, Qing Shen, and Shuzi Hayase

ACS Applied Materials & Interfaces 2023 15 (35), 41549-41559

https://doi.org/10.1021/acsami.3c08655

This research focuses on enhancing the efficiency of wide bandgap lead halide perovskite solar cells (WBG Pb-PVK PSCs) using FA0.8Cs0.2PbI1.8Br1.2 as the light-harvesting layer. By passivating the hydrophobic surface of the hole transporting layer (PTAA) with a monomolecular layer, improved hydrophilicity and band alignment result in WBG Pb-PVK PSCs achieving an impressive 16.52% efficiency at 1.77 eV.

How Paios was used

MS curves, EIS, TPC, and TPV results were all performed using Paios from Fluxim

Ali, U., Javed, S., Qureshi, A. A., Akram, M. A.,

Chem Nano Mat 2023, 9, e202300175.

https://doi.org/10.1002/cnma.202300175

This research discusses the use of an interlayer of aluminum-doped zinc oxide (AZO) nanoparticles to suppress interfacial recombination and improve the performance and stability of perovskite solar cells. The PCBM/AZO electron transport bilayer with an optimal concentration of 2% Al dopant exhibited greatly improved power conversion efficiency (PCE) of 18.63%, VOC of 1.13 V, and FF of 73% with negligible hysteresis index of 0.04.

How Paios was used

The TPC, TPV, and impedance measurements were performed using PAIOS from Fluxim. A pulse intensity for an optimized period was used to induce a spike in photovoltage and photo-current subsequently. The impedance spectra were taken from PAIOS v. 4.4 software, and scans were taken from 10 Hz to 2 MHz at a 0 V bias in the dark.

M. Battaglia, E. Comi, T. Stadelmann, R. Hiestand, B. Ruhstaller, E. Knapp;

APL Mach. Learn. 1 September 2023; 1 (3): 036108.

https://doi.org/10.1063/5.0139707

A data-driven approach using deep learning predicts parameters of a solar cell model based on electroluminescence (EL) images. Using 75,000 synthetic EL images, the study employs a deep ensemble of 17 modified VGG19 neural networks to add uncertainty estimates. This approach, tested on four solar cell samples, bridges deep learning with engineering applications needing real-time physical model parameterizations with confidence intervals. The network's predictions showed an average deviation of 0.2% (max 10%) in junction voltage values, confirming the method's validity.

How Laoss was Used

Laoss, a simulation model, was used to model the measured solar cell samples and generate simulated electroluminescence (EL) images. These images were then used to train the inverse convolutional neural network (CNN) model. The Laoss parameterization used to generate the training data is discussed in the paper. The inverse model was trained on a set of simulated EL images, and the network architecture and training of the inverse CNN model are explained in detail. The results of the inverse model method are evaluated, and the changes in the CNN structure and training hyperparameters required to implement and train such a deep ensemble CNN inverse model are discussed.

Montecucco, R., Pica, G., Romano, V., De Boni, F., Cavalli, S., Bruni, G., Quadrivi, E., De Bastiani, M., Prato, M., Po, R. and Grancini, G. (2023),

Sol. RRL 2300358.

https://doi.org/10.1002/adfm.202306040

All-inorganic perovskites show potential for creating stable and high-performing perovskite solar cells (PSCs). But, the high annealing temperature required for CsPbI3 stabilization limits its scalability for industrial production. This research introduces a method to stabilize CsPbI3ₓBrx perovskite at a reduced annealing temperature of 180°. This is achieved by using dimethylammonium (DMA) additives and bromide, facilitating the conversion to CsPbI3ₓBrx. Solar cells produced this way reached a power conversion efficiency (PCE) of 14.86%, outperforming the reference device. Using different halides in DMA salt for higher temperature annealing also proved beneficial, yielding an impressive PCE of 16.23%. This method, by lowering processing temperature, extends the utility of all-inorganic PSCs for industrial use and temperature-sensitive materials.

How Litos Lite was used

The stability measurements were performed at the MPP under N2 inert atmosphere and ambient temperature using Litos Lite coupled with a solar simulator continuously illuminating the devices. The spectrum used for the stability measurements was the same as the current density–voltage measurements.

Juanita Hidalgo, Lahoucine Atourki, Ruipeng Li, Andrés-Felipe Castro-Méndez, Sanggyun Kim, Emmet A. Sherman, Alexander S. Bieber, Meng-ju Sher, Lea Nienhaus, Carlo A.R. Perini, Juan-Pablo Correa-Baena,

Materials Today, Volume 68, 2023, Pages 13-21, ISSN 1369-7021,

https://doi.org/10.1016/j.mattod.2023.06.010

Interfacial treatments using bulky cations on 3D lead halide perovskites (LHPs) have led to over 25% power conversion efficiencies, but the reasons for this boost remain unclear. This study zeroes in on formamidinium lead iodide (FAPI) perovskites and shows that phenethylammonium iodide (PEAI) prevents the FAPI from changing into less desirable hexagonal forms in air exposure. Using advanced analytical methods, researchers discovered that untreated FAPI films predominantly show these undesired hexagonal phases. However, when coated with PEAI, FAPI films exhibit improved carrier lifetimes and photoconductivity. Such PEAI-treated FAPI solar cells can achieve up to 20.2% efficiency and 1.14 V open circuit voltages, marking one of the top performances for FAPI cells without extra cations.

How Litos Lite was used

Solar cell performance was evaluated under a solar simulator LITOS LITE from Fluxim, with AM1.5 spectrum, same light intensity for the maximum power point tracking for 180 s. The current density–voltage (JV) curve was measured in a forward and reverse bias at a scan rate of 50 mV/s. The cells were masked for measurement with a pixel area of 0.0625 cm2. Nitrogen was flown in the measurement chamber during characterization.

Larini, V., Ding, C., Faini, F., Pica, G., Bruni, G., Pancini, L., Cavalli, S., Manzi, M., Degani, M., Pallotta, R., De Bastiani, M., Ma, C.-Q., Grancini, G

Adv. Funct. Mater. 2023, 2306040.

https://doi.org/10.1002/adfm.202306040

Transparent conductive oxide (TCO)-coated glasses are a costly and environmentally impactful part of perovskite solar cells (PSCs), accounting for 56% of their total cost and 96% of their carbon footprint. Recycling TCO glasses from old PSC modules can reduce both their cost and energy payback time. In this study, tin oxide (SnO2)-coated indium tin oxide glasses are refurbished using eco-friendly dimethyl sulfoxide as a solvent. The reclaimed substrates are used to create new-generation PSCs with the same high efficiency of 22.6%, and even higher average efficiency, thanks to surface modifications and trap passivation on the SnO2/perovskite interface.

How Litos Lite was used

Stability measurements were conducted by coupling a WavelabsSINUS-70 solar simulator with a Fluxim Litos Lite module and perform-ing maximum power point tracking for 1000 h under an N2atmosphere at1 sun illumination, employing a shadow mask of 1.25 mm2active area.

Sandheep Ravishankar, Zhifa Liu, Yueming Wang, Thomas Kirchartz, and Uwe Rau

PRX Energy 2, 033006 – Published 2 August 2023

https://doi.org/10.1103/PRXEnergy.2.033006

Researchers present a model for the frequency and time domain optoelectronic response of perovskite solar cells (PSCs). The model emphasizes the role of charge carrier exchange between the perovskite and the transport layer. The study identifies that the time constants measured in the frequency domain spectra of PSCs are mainly influenced by the charge carrier extraction velocity at the perovskite/transport layer interfaces, rather than recombination. This understanding is crucial for quantifying recombination and resistive losses that impact the performance of the solar cell.

Drift-diffusion simulations are performed using SETFOS developed by Fluxim AG

Li, G., Pu, J., Yang, Z., Deng, H., Liu, Y., Mao, Z., Zhao, J., Su, S., Chi, Z., Aggregate 2023, 00, e382.

https://doi.org/10.1002/agt2.382

This study proposes a design strategy for constructing highly efficient organic light-emitting diodes (OLEDs) using thermally activated delayed fluorescence (TADF) emitters with high horizontal dipole ratios. The researchers designed two TADF emitters, BO-3DMAC and BO-3DPAC, using a shamrock-shaped structure. These emitters exhibited high horizontal dipole ratios of 84-93% in both neat and doped films. The emitters showed excellent external quantum efficiencies (EQEs) of up to 38.7% in doped OLEDs with sky-blue emission. The researchers also demonstrated that the shamrock-shaped design resulted in aggregation-induced emission (AIE) and low efficiency roll-off. The emitters had low singlet-triplet energy splitting (ΔEst) and achieved high PLQYs. The results highlight the potential of the shamrock-shaped design to construct TADF emitters with high Θ// and pave the way for the development of high-performance OLEDs.

How Setfos was used

The refractive index of the materials were extracted from the Setfos database and the light out-coupling efficiency of devices were also simulated.

Bi, H., Fujiwara, Y., Kapil, G., Tavgeniene, D., Zhang, Z., Wang, L., Ding, C., Sahamir, S. R., Baranwal, A. K., Sanehira, Y., Takeshi, K., Shi, G., Bessho, T., Segawa, H., Grigalevicius, S., Shen, Q., Hayase, S.,

Adv. Funct. Mater. 2023, 33, 2300089.

https://doi.org/10.1002/adfm.202300089

This research discusses the enhancement of perovskite solar cells (PSCs) by modifying the hole transport layer (HTL) with a monomolecular layer (MNL). The researchers focused on improving the efficiency of wide bandgap perovskite solar cells used in perovskite/perovskite tandem solar cells. They found that surface-modifying PTAA (poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine]) with MNL improved PSC efficiency by enhancing perovskite film quality, reducing distortion, and decreasing charge recombination sites. The length of the alkyl group in the MNL also influenced the efficiency of the PTAA layer. The PTAA/monomolecular bilayer achieved a power conversion efficiency of 16.57% in wide bandgap lead PSCs. Furthermore, the PTAA/monomolecular substrate enabled all-perovskite tandem solar cells with over 25% efficiency. These findings demonstrate the potential of MNL modification for improving perovskite solar cell efficiency.

How Paios was used

Electrochemical impedance spectroscopy (EIS), Transient photovoltaic voltage (TPV), and Transient photovoltaic current (TPC) were carried out using Paios with an LED light.

Juanita Hidalgo, Yu An, Dariia Yehorova, Ruipeng Li, Joachim Breternitz, Carlo A.R. Perini, Armin Hoell, Pablo P. Boix, Susan Schorr, Joshua S. Kretchmer, and Juan-Pablo Correa-Baena

Chemistry of Materials 2023 35 (11), 4181-4191

DOI: 10.1021/acs.chemmater.3c00075

This scientific article investigates the factors that determine crystallographic orientation in lead bromide perovskites. The researchers show that the solvent and organic A-site cation play a critical role in preferred orientation of the thin films. The results reveal that the solvent, specifically dimethylsulfoxide (DMSO), influences the early stages of crystallization and induces preferred orientation by preventing colloidal particle interactions. Additionally, the choice of A-site cation, such as methylammonium or formamidinium, affects the degree of preferred orientation. Density functional theory calculations suggest that the difference in surface energy between the (100) and (110) facets is the reason for the varying degrees of preferred orientation. Besides, the researchers observe that the choice of A-site cation impacts ion density and accumulation, leading to increased hysteresis in solar cells. Overall, this study highlights the importance of solvent and A-site cation in determining crystallographic orientation and its impact on the electronic and ionic properties of solar cells.

How Litos Lite & Paios were used

LITOS LITE was used to measure the current density-voltage (J-V) characteristics of the solar cells. The J-V curves were obtained by scanning voltage in the range from 1.4 to -0.5 V with a scan speed of 50 mV·s-1 first in reverse and then in forward scan directions. The active area of the device was 0.128 cm2, and a black metal mask with an aperture area of 0.0625 cm2 was used to define the illuminated area.

Impedance Spectroscopy: #PAIOS was used to perform Impedance Spectroscopy (IS) on complete solar cells at room temperature under one sun illumination and in ambient air. The measurements were performed at five different offset voltages spaced from 0 V to the open circuit.

Wang, J, Xie, M, Pang, H, Zhang, C, Sang, M, Zhang, Q, et al.

J Soc Inf Display. 2023; 31( 6): 457– 465.

https://doi.org/10.1002/jsid.1205

This scientific article discusses the development of high-performance red and green phosphorescent emitters suitable for the BT.2020 color gamut in displays. The researchers conducted optical simulations to determine the optimal spectra for the emitters. For the green emitter, they found that a spectrum with a peak wavelength at 526 nm and a full width at half maximum (FWHM) less than 30 nm could achieve the desired color coordinates. For the red emitter, they discovered that decreasing the FWHM instead of red-shifting the spectrum was important to achieve the desired color coordinates while maintaining high current efficiency. Based on these simulation results, the researchers designed and synthesized novel deep green (DGD) and deep red phosphorescent (DRD-II) emitters. The DGD emitter achieved a color coordinate of (0.170, 0.777) with a current efficiency of 171 cd/A, and the DRD-II emitter achieved a color coordinate of (0.708, 0.292) with a current efficiency of 59 cd/A. The researchers also demonstrated that the angular dependence of these devices was comparable to those with commercial emitters. Overall, these findings suggest that phosphorescent emitters have the potential to meet the BT.2020 color standard in organic displays.

How was Setfos used?

SETFOS 5.0 was used for optical simulations to determine the optimal spectrum of a green emitter suitable for BT.2020. The simulations involved employing a series of simulated green photoluminescence (PL) spectra. Optical constants, such as the refractive index and the extinction coefficient of each emitter, were taken into account during the simulations.

Jonas Diekmann, Francisco Peña-Camargo, Nurlan Tokmoldin, Jarla Thiesbrummel, Jonathan Warby, Emilio Gutierrez-Partida, Sahil Shah, Dieter Neher, and Martin Stolterfoht

The Journal of Physical Chemistry Letters 2023 14 (18), 4200-4210

DOI: 10.1021/acs.jpclett.3c00530

This scientific article discusses the impact of mobile ions on perovskite photovoltaic devices and the challenges in accurately quantifying mobile ion densities. The study evaluates several experimental methodologies, including charge extraction by linearly increasing voltage (CELIV) and bias-assisted charge extraction (BACE), as well as frequency-dependent capacitance measurements.

The findings show that CELIV underestimates ion density and is not suitable for accurate quantification. BACE, on the other hand, can accurately reproduce ion density as long as it is lower than the electrode charge. The study also demonstrates that low-frequency Mott-Schottky analysis can provide accurate ion density values for high excess ionic densities typical of perovskites. Overall, the methods presented in this study enable accurate tracking of ionic densities in perovskite devices and a deeper understanding of ionic losses and device aging.

How was Setfos Used?

SETFOS was used in this work to simulate the impact of mobile ions on the performance of perovskite solar cells. The parameters related to mobile ions were implemented in the drift-diffusion module of Setfos. This allowed the researchers to include mobile ions in their simulations and recreate the observed JV-hysteresis in the cells over a wide range of scan speeds. The simulations also verified that losses in the performance characteristics of JSC, VOC, and FF could be recreated

Kamijo, T., van Breemen, A.J.J.M., Ma, X. et al. A touchless user interface based on a near-infrared-sensitive transparent optical imager. Nat Electron (2023).

https://doi.org/10.1038/s41928-023-00970-8

Researchers have developed a touchless user interface based on a visually transparent near-infrared-sensitive organic photodetector (OPD) array. The touchless interface can be used on top of a display, eliminating the need for physical contact.

The OPD array is designed with optical transparency in mind, using printed copper grids and patterned organic photodetector subpixels. The design optimization results in a high photodetectivity of 10^12 Jones at 850 nm and a visible-light transmittance of 70%.

The touchless user interface can be used with a penlight or through gesture recognition, providing a hygienic and convenient alternative to traditional touch screens. The technology has potential applications in automated teller machines (ATMs), ticket vending machines, and kiosks, where hygiene is a concern. It is a scalable and flexible solution that can be integrated into a variety of display applications without size limitations or calibration requirements. 2D FEM simulations for the surface potential and the current density distributions derived from the printed Cu grid structure .

How Fluxim’s Research Tools were used

Setfos

Numerical electro-optical simulations for the photogenerated J–V curves of our NIR-sensitive OPDs were performed by using Setfos.

The VLT of the parallel OPD subpixel array was calculated by the summation of the simulated optical transmittance for each component using Setfos

Laoss

2D FEM simulations for the surface potential and the current density distributions derived from the printed Cu grid structure for our NIR-sensitive OPDs were performed by Laoss 4.0

haoyang Wang et al 2023 J. Phys. Mater. 6 024004

DOI 10.1088/2515-7639/accaaa

Indoor photovoltaic devices using halide perovskites are studied for their potential in powering IoT applications. CH3NH3PbI3-based devices with Spiro-OMeTAD and P3HT as hole transport layers were compared, and Spiro-OMeTAD showed higher power conversion efficiency. The best-performing Spiro-OMeTAD device successfully powered a wearable motion sensor, demonstrating the potential for self-sufficient sensor systems.

Light intensity-dependent J-V measurement, transient photovoltage (TPV) and transient photocurrent (TPC) measurement were carried out with the characterization platform, Paios, Fluxim AG, Switzerland.

Metikoti Jagadeeswararao, Kyu Min Sim, Sangjun Lee, Mingyun Kang, Sanghyeok An, Geon-Hee Nam, Hye Ryun Sim, Elham Oleiki, Geunsik Lee, and Dae Sung Chung

Chemistry of Materials 2023 35 (8), 3095-3104

DOI: 10.1021/acs.chemmater.2c03271

This study demonstrates high-performance photomultiplication (PM)-type photodetectors using lead-free double perovskite, achieved by engineering trap states and trap-assisted charge injection. With a diode structure, the researchers realized selective hole traps, leading to high external quantum efficiency (EQE) of ∼16,000%, responsivity of ∼50 A W−1, and specific detectivity over 10¹² Jones at -3V. The work highlights PM photodetectors' potential through strategic trap engineering.

Setfos, a Fluxim software, was used for drift-diffusion simulations to gain comprehensive insight into the photomultiplication mechanism in the proposed photodetector.

Ràfols-Ribé, J., Hänisch, C., Larsen, C., Reineke, S. and Edman, L. Adv. Mater. Technol. 2202120.

https://doi.org/10.1002/admt.202202120

This study explores emissive dipole orientation in light-emitting electrochemical cells (LECs) affecting emission efficiency. Using a destructive-interference microcavity method, researchers find ≈95% horizontal dipole orientation in LECs with Super Yellow emitters, enabling efficient photon outcoupling, despite strong perpendicular electric fields and ion motion.

LEC Optical Modeling and Fitting: The LEC devices were simulated with a Setfos.

Yi Yang, Jingwen Wang, Yunfei Zu, Qing Liao, Shaoqing Zhang, Zhong Zheng, Bowei Xu, Jianhui Hou,

Robust and hydrophobic interlayer material for efficient and highly stable organic solar cells,

Joule, Volume 7, Issue 3, 2023, Pages 545-557, ISSN 2542-4351,

https://doi.org/10.1016/j.joule.2023.02.013

A robust, hydrophobic electron transporting interlayer for organic solar cells (OSCs) is designed using a cross-linkable naphthalene diimide (NDI) derivative. The non-polar electron donor PCy2 is used to n-dope the crosslinked c-NDI:PCy2 film, increasing its doping density and conductivity.

This hydrophobic interlayer protects the device against water, resulting in excellent water resistance. With the c-NDI:PCy2 interlayer, a power conversion efficiency of 17.7% is achieved, which is the highest for OSCs with an inverted device architecture. Notably, this OSC can be used underwater, maintaining 70% of its initial efficiency after 1,000 hours in the dark or 4 hours under continuous illumination.

Paios was used to perform CELIV and TPV measurements.

Seriwattanachai, C., Kaewprajak, A., Sukgorn, N. et al.

Journal of Materials Research (2023).

https://doi.org/10.1557/s43578-023-00967-1

This study developed dual electron transport layers (TiO2/WO3:AgInS2 QDs) for planar perovskite solar cells, which improved charge extraction and transportation. AgInS2 quantum dots were fabricated with varying sizes, resulting in a redshift in the photoluminescence (PL) peak intensity.

The addition of AgInS2 QDs quenched the PL intensity of the perovskite film. Improved device stability was achieved due to the WO3:AgInS2 QDs layer, which protected the perovskite interface from direct contact with TiO2 and prevented UV decomposition. The TiO2/WO3:AgInS2 QDs electron transport layers enhanced the performance and long-term stability of perovskite solar cells.

The electrochemical impedance spectroscopy (EIS), intensity modulated photovoltage spectroscopy (IMVS) and intensity modulate photocurrent spectroscopy (IMPS) were measured by PAIOS.

Li, B., Huang, X., Wu, X., Zuo, Q., Cao, Y., Zhu, Q., Li, Y., Xu, Y., Zheng, G., Chen, D., Zhu, X.-H., Huang, F., Zhen, H., Hou, L., Qing, J., Cai, W., Adv. Funct. Mater. 2023, 2300216. https://doi.org/10.1002/adfm.202300216

Q-2D perovskites are promising photodetector materials, but their charge transport is limited by their hybrid low-dimensional structure. Researchers used a double-hole transport layer (PTAA & PEDOT:PSS) to create evenly-distributed 3D-like phases with vertical orientation, improving charge transport and reducing recombination.

This Ruddlesden-Popper perovskite photodetector achieved a high responsivity, specific detectivity, linear dynamic range, and fast rise/fall times. The study reveals the relationship between Q-2D perovskites' phase structure and performance, guiding future photodetector designs.

Transient photovoltage decay (TPV) measurements were performed with PAIOS instrumentation.

Qiang Guo, Zheng Dai, Chuanqi Dong, Yuanjia Ding, Naizhong Jiang, Zhibin Wang, Lei Gao, Chen Duan, Qing Guo, Erjun Zhou,

17.3% efficiency CsPbI2Br solar cells by integrating a Near-infrared absorbed organic Bulk-heterojunction layer,

Chemical Engineering Journal, Volume 461, 2023, 142025, ISSN 1385-8947,

https://doi.org/10.1016/j.cej.2023.142025.

All-inorganic perovskite solar cells (PSCs) offer excellent thermal stability, but lag in power conversion efficiency compared to hybrid PSCs. Researchers integrated a low bandgap organic active layer (PM6:Y6) to CsPbI2Br PSCs, extending the photo-response range, improving short-circuit current density, and boosting efficiency from 15.31% to 17.33%. This promising strategy demonstrates enhanced performance and deeper understanding of carrier transfer in integrated solar cells.

Transient photovoltage (TPV) and transient photocurrent (TPC) were performed on a Fluxim Paios characterization system with light intensity about 0.278 sun.

Zheng Dai, Qiang Guo, Yuanjia Ding, Zhibin Wang, Naizhong Jiang, and Erjun Zhou

ACS Appl. Mater. Interfaces 2023, 15, 7, 9784–9791

Publication Date:February 9, 2023

https://doi.org/10.1021/acsami.2c23036

Efficient and stable perovskite solar cells (PSCs) rely heavily on hole-transporting materials (HTMs), with dopant-free conjugated polymers gaining interest for their high hole mobility and stability. A recent study explored the relationship between polymer structure and photovoltaic performance by using three D-π-A-type polymers with varying A units.

The energy levels, hole mobility, molecular stacking, and charge transfer were investigated for CsPbI2Br PSCs with these HTMs. The device using PE61 HTM achieved the highest power conversion efficiency at 16.72%, outperforming PBDB-T (15.13%) and J52 (15.52%), and exhibited the best long-term stability.

This demonstrates that quinoxaline is an effective A unit for D-π-A-type polymers, improving PSC photovoltaic performance.

Transient photocurrent (TPC) and transient photovoltage (TPV) were tested by a Fluxim Paios characterization system.

Muhammad Abdel-Shakour, Kiyoto Matsuishi, Towhid H. Chowdhury, Ashraful Islam,

Solar Energy Materials and Solar Cells,

Volume 254, 2023, 112241, ISSN 0927-0248,

https://doi.org/10.1016/j.solmat.2023.112241.

Researchers are exploring Sn-based perovskite solar cells as a non-toxic alternative, but challenges remain due to oxidation and moisture permeation. A recent study used a Lewis base additive, formamidinesulfinic acid (FASO2H), to address these issues. Results showed a 32% reduction in Sn2+/Sn4+ oxidation, improved crystallinity, and a 66% decrease in lattice strain. The modified cells achieved a 7.44% power conversion efficiency and demonstrated superior moisture protection and light soaking stability, retaining 90% of initial efficiency after 450 hours.

Dark J-V and EIS for the fabricated PSCs were calculated using Paios.

Chu, X., Ye, Q., Wang, Z. et al.

Nat Energy (2023).

https://doi.org/10.1038/s41560-023-01220-z

Researchers developed a surface in situ reconstruction (SISR) strategy using CsF treatment to improve all-inorganic perovskite solar cells. The treatment suppresses non-radiative recombination, passivates surface defects, and promotes hole extraction. It results in a longer carrier lifetime and creates a graded heterojunction. As a result, CsPbIxBr3−x solar cells with SISR achieve a 21.02% efficiency, a 1.27 V open-circuit voltage, and an 85.3% fill factor. This work offers an effective approach to enhance inorganic perovskite surfaces for efficient solar cells.

Electrical impedance spectroscopy (EIS), capacitance–voltage (C–V) and photogenerated charge extraction by linearly increasing voltage (photo-CELIV) mobilities data were measured by the all-in-one characterization platform Paios (Fluxim AG) in air conditions without encapsulation.

Park, Y., Lee, G.S., Lee, W. et al.

Sci Rep 13, 1369 (2023).

https://doi.org/10.1038/s41598-023-27487-6

Researchers have designed Ir(III)-based heteroleptic NIR materials for near-infrared organic light-emitting diodes (NIR OLEDs) with a focus on radiance capacity (RC) rather than just radiance. The emitters exhibit a highly oriented horizontal dipole ratio, short radiative lifetime, and extremely low turn-on voltage.

The device demonstrates a high RC of 720 mW/sr/m2/V, making it a standout performer among Ir(III)-based NIR OLEDs with similar emission peaks, and has potential applications in healthcare, authentication, and night vision displays.

Measurement of the angle dependent p‑polarized photoluminescent spectrum (ADPL). The emission layer was deposited on a bare 50 nm-thick glass substrate. Then, glass encapsulation was done in a nitrogen ( N2)-filled glove box to avoid degradation from the air. A full angle dependent p-polarized PL spectrum was obtained with the goniometer based motorized intensity measurement system Phelos.

Lee, J. H., Huang, J.-X., Chen, C.-H., Lee, Y.-T., Chan, C.-Y., Dzeng, Y.-C., Tang, P.-W., Chen, C., Adachi, C., Chiu, T.-L., Lee, J.-H., Chen, C.-T.,

Adv. Optical Mater. 2023, 2202666.

https://doi.org/10.1002/adom.202202666

Researchers have designed and synthesized a novel near-ultraviolet (NUV) fluorescent material, BB4Ph, based on the classic 1,1′:4′,1″-terphenyl fluorophore. The material exhibits high order and horizontal-dipole ratios, enabling efficient NUV organic light-emitting diodes (OLEDs). Non-doped BB4Ph OLEDs achieved external quantum efficiency (EQE) up to 5.24%, while doped BB4Ph OLEDs with 4P-Cz reached a peak EQE of 6.99%. The material's high photoluminescence quantum yield and light outcoupling efficiency make it a promising candidate for NUV OLED applications.

Hsieh CA, Tan GH, Chuang YT, Lin HC, Lai PT, Jan PE, Chen BH, Lu CH, Yang SD, Hsiao KY, Lu MY, Chen LY, Lin HW.

Adv Sci (Weinh). 2023 Feb 7:e2206076.

doi: 10.1002/advs.202206076

Researchers have significantly improved the efficiency of vacuum-deposited metal halide perovskite light-emitting diodes (PeLEDs) by optimizing the stoichiometric ratio of sublimed precursors and incorporating ultrathin layers. The properties of these perovskite layers are highly influenced by the presence of upper- and presublimed materials, which helps enhance device performance. By eliminating Pb° formation and passivating defects, the PeLEDs achieve an impressive external quantum efficiency (EQE) of 10.9% and up to 21.1% when integrating a light out-coupling structure.

The optical simulation of PeLEDs was done with SETFOS.

Kuo, H.-H., Kumar, S., Omongos, R. L., T. do Casal, M., Usteri, M. E., Wörle, M., Escudero, D., Shih, C.-J.,

Adv. Optical Mater. 2023, 2202519.

https://doi.org/10.1002/adom.202202519

Researchers have developed efficient phosphorescent emitters using abundant Au(III) complexes with asymmetric C^C^N ligands and carbazole moieties. The synthesized complexes exhibit shortened radiative lifetimes and high photoluminescence quantum yields, reaching over 93% in thin films. As a result, high-performance OLED devices demonstrate record-high external quantum efficiencies and current efficiencies, paving the way for the molecular design of anisotropic Au(III) emitters in next-generation optoelectronics.

The researchers quantified the horizontal dipole ratios in thin-films using the angular-dependent PL spectroscopy by fitting the experimental p-polarized (p-pol) angular PL intensity as a function of viewing angle with optical simulations using Setfos.

Tianqi Zhang,Pai Liu, Fangqing Zhao, Yangzhi Tan, Jiayun Sun, Xiangtian Xiao, Zhaojing Wang, Qingqian Wang, Fankai Zheng, Xiao Wei Sun, Dan Wu, Guichuan Xing and Kai Wang

Nanoscale Adv., 2023, 5, 385

https://doi.org/10.1039/d2na00705c

Researchers introduced an electric dipole layer in green InP QLEDs to enhance hole injection and balance carrier injection. This approach increased the carrier recombination rate, resulting in a high luminance of 52,730 cd m−2 and a 1.7 times EQE enhancement from 4.25% to 7.39%, paving the way for highly efficient green InP QLEDs.

Electrical simulations were performed with Setfos, while the constant or field-dependent electron and hole mobilities according to the Poole–Frenkel model were used in the simulations.

Researchers have made significant advancements in enhancing the efficiency of organic light-emitting diodes (OLEDs) by addressing two major light loss channels: substrate guided modes and evanescent modes. By micromachining hole patterns with specific characteristics onto the air/glass side of the OLED substrate, they achieved a 60% enhancement in light outcoupling efficiency (ηout) while reducing viewing angle dependence. This innovative approach prevents total internal reflection events and minimizes interference effects, improving OLEDs' general lighting applications.

In addition, a materials engineering approach was used to reduce losses to evanescent modes by employing π-conjugated polymers in the emissive layer. These polymers naturally emit TE-polarized radiation, reducing losses and enhancing ηout. The researchers developed a novel solution withdrawal coating (SWC) technique to simultaneously deposit the polymer film and control uniaxial orientation, resulting in highly efficient OLED displays with linearly polarized luminescence. This groundbreaking work paves the way for further advancements in the OLED technology, making it more efficient and versatile for various applications.

SETFOS was used to simulate the mode contributions within the OLED and optimize the dimensions of the glass patterns made at the air/substrate interface.

Jingwen Feng, Maocheng Jiang, Dong Li, Yuanming Zhang, Chen Pei, Li Zhou, Zhuo Chen, Yanzhao Li, Xinguo Li, and Xiaoguang Xu

The Journal of Physical Chemistry Letters 2023 14 (10), 2526-2532

https://doi.org/10.1021/acs.jpclett.3c00307

High-performance, eco-friendly heavy metal-free (HMF) quantum dot LEDs are vital for next-gen displays. ZnSeTe/ZnSe/ZnS blue QDs achieve adjustable energy levels & emission peaks, yielding a peak CE of 11.8 cd A−1. Optimizing chroma efficiency, these QLEDs offer 2.2x improvement over control devices.

SETFOS simulation software was utilized to assist in determining the optimal optical structure of the device, and we find that the emission intensity and peak position can be better matched in ZnSe:0.0385Te/ZnSe/ZnS-based QLED.

Huo, M.; Hu, Y.; Xue, Q.; Huang, J.; Xie, G.

Molecules 2023, 28, 2145.

https://doi.org/10.3390/molecules28052145

Organic/inorganic hybrid materials, like PVA and TTIP, show excellent optical properties for multilayer antireflection films. With a tunable refractive index & low haze, they achieve high transmittances up to 99.3%. Applied to perovskite solar cells, they boost efficiency from 16.57% to 17.25%.

The hybrid material/CA stack and the hybrid material/PMMA stack were simulated by Setfos.

Yun Hu, Jing-song Huang, Paul N. Stavrinou, Donal D. C. Bradley, Proc. SPIE 12314, Optoelectronic Devices and Integration XI,

123140O (20 December 2022); doi: 10.1117/12.2641624

Organic-oxide hybrid DBRs achieve high conductivity & light manipulation in organic optoelectronic devices. MoO3 doping increases TAPC conductivity by 10,000x with minimal refractive index change. Integrated OLEDs with bottom conductive DBRs demonstrate light regulation at low voltage.

The optical simulations of DBR and OLED devices were performed by using a commercially available SETFOS (Fluxim) program. The refractive index, extinction coefficient (k), photoluminescence (PL) spectrum of emissive layers and thickness of each layer were used as input parameters. Transfer matrix method (TMM) and Gaussian dipole distribution dipole emitter as source are used in simulation.

Aeberhard, U., Zeder, S.J. & Ruhstaller, B.

Opt Quant Electron 54, 617 (2022).

https://doi.org/10.1007/s11082-022-03791-9

The impact of photon recycling on the efciency of light extraction from metal halide perovskite light emitting diodes is quantifed using a novel modelling framework based on a detailed-balance compatible Green dyad approach. Analysis of photon modes contributing to internal emission and iterative evaluation of re-absorption and re-emission processes is performed for single perovskite layers in absence and presence of a metallic refector and under consideration of associated parasitic absorption losses. Finally, the approach is employed to characterize the emission characteristics of a realistic multilayer device stack in dependence of the emitter thickness.

The photon recycling simulation was performed with Setfos.

Kuo-Hsien Chou, Tun-Hao Chen, Xian-Qing Huang,a Chia-Sheng Huang, Chih-Hao Chang, Chien-Tien Chen and Jwo-Huei Jou

Mater. Adv., 2023,4, 1335-1344

DOI: 10.1039/d2ma00974a

Organic light-emitting diodes (OLEDs) are increasingly used in display technology and lighting, with a need for better electron-transporting materials (ETMs) for higher efficiency and longer lifetimes. Researchers synthesized four seven-member-ring-based ETMs, finding that using 2′,12-di(pyridin-4-yl)spiro[dibenzo[3,4:5,6]cyclohepta[1,2-b]pyridine-9,9′-fluorene] (DPP) as an ETM increased green OLED efficiency by 39% and device lifetime by 43% compared to 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBi).

The improvements were attributed to DPP's higher electron mobility and deeper highest occupied molecular orbital (HOMO) level. However, DPP was unsuitable for blue phosphorescent emitters, but another synthesized ETM, 4-(spiro[dibenzo[3,4:5,6]cyclohepta[1,2-b]pyridine-9,9′-fluoren]-12-yl)benzonitrile (PC), increased blue OLED efficiency by 46% compared to TPBi.

The recombination rate of the studied OLEDs were obtained by using electrical simulation software SETFOS.

Salem, M.S.; Shaker, A.; Abouelatta, M.; Saeed, A.

Polymers 2023, 15, 784.

https://doi.org/10.3390/polym15030784

Researchers have designed and analyzed perovskite/organic tandem solar cells (TSCs) using a full optoelectronic simulator (SETFOS).

A lead-free ASnI2Br perovskite top subcell is paired with a DPPEZnP-TBO:PC61BM heterojunction organic bottom subcell, based on previous experimental work. Calibration shows strong agreement between simulation and experimental data.

The optimized tandem cell achieves 14% efficiency with further improvements possible through concurrent optimization and defect reduction. This study provides valuable insights and directions for enhancing lead-free perovskite/organic TSC efficiency.

Pietro Caprioglio, Joel A. Smith, Robert D. J. Oliver, Akash Dasgupta, Saqlain Choudhary, Michael D. Farrar, Alexandra J. Ramadan, Yen-Hung Lin, M. Greyson Christoforo, James M. Ball, Jonas Diekmann, Jarla Thiesbrummel, Karl-Augustin Zaininger, Xinyi Shen, Michael B. Johnston, Dieter Neher, Martin Stolterfoht & Henry J. Snaith

Nat Commun 14, 932 (2023).

https://doi.org/10.1038/s41467-023-36141-8

Wide-gap perovskites suffers from Voc- and Jsc-deficit, but what's the reason and how to solve it?

Researchers from the groups of professors Henry J. Snaith and Martin Stolterfoht recently demonstrated starting from drift-diffusion simulation studies that a poor band-alignment with the electron transporting layer causes the Voc-deficit, while mobile ions obstacle the charge extraction causing Jsc losses. The voltage losses were solved by inducing the growth of a low-dimensional perovskite with a surface treatment based on guanidinium bromide (GuaBr) or imidazolium bromide (ImBr). To improve the charge extraction, they modified the hole-transporting layer applying an ionic interlayer (TEA-TFSI) or replaced it with self-assembled monolayer (SAM).

They used the simulation software Setfos from Fluxim AG to reveal that the hole-transporting layers enhance the charge extraction by inducing a stronger electric field at the interface with the perovskite.

Park, Y., Lee, G.S., Lee, W. et al.

Sci Rep 13, 1369 (2023).

https://doi.org/10.1038/s41598-023-27487-6

Researchers have developed new Ir(III)-based heteroleptic NIR materials for near-infrared organic light-emitting diodes (NIR OLEDs) with heavy metals, which have a highly oriented horizontal dipole ratio and short radiative lifetime. These emitters offer an extremely low turn-on voltage and high radiance capacity, making them suitable for various applications such as healthcare services, veil authentication, and night vision displays. This study demonstrates exceptional device performance among similar Ir(III)-based NIR OLEDs, which makes it a promising material for commercial applications.

Measurement of the angle dependent p-polarized photoluminescent spectrum (ADPL)

The emission layer was deposited on a bare 50 nm-thick glass substrate. Then, glass encapsulation was done in a nitrogen (N2)-filled glove box to avoid degradation from the air. A full angle dependent p-polarized PL spectrum was obtained with the goniometer based motorized intensity measurement system Phelos, Fluxim.

Liu, Y., Yang, J., Mao, Z., Ma, D., Wang, Y., Zhao, J., Su, S.-J., Chi, Z.,

Adv. Optical Mater. 2023, 2201695

DOI: 10.1002/adom.202201695

The article reports on the development of three thermally-activated delayed fluorescence (TADF) molecules with different donor-acceptor (D-A) frameworks, namely D-A, D-A-D, and D-A-A. The TADF molecules were evaluated for their photophysical and electroluminescence properties. The study found that the TADF molecule with the D-A-A framework achieved the best performance in terms of external quantum efficiency due to its low energy gap between singlet and triplet, effective reverse intersystem crossing, high photoluminescence quantum yield, and horizontal dipole ratio. The study provides insights into the design of efficient TADF emitters.

P-polarized angle-dependent light emissions of CBP doped films were measured by Fluxim using Phelos. Refractive index of the materials was measured by MEL broadband spectroscopic Mueller matrix ellipsometer or extracted by Setfos database. The light out-coupling efficiency of devices was simulated by Setfos.

Can Zhu, Ke Hu, Lei Meng, Xiaolei Kong, Wenbin Lai, Shucheng Qin, Beibei Qiu, Jinyuan Zhang, Zhanjun Zhang, Yilei Wu, Xiaojun Li, and Yongfang Li

CCS Chem. Jan 4, 2023,

DOI: 10.31635/ccschem.022.202202491

Researchers have developed a new D-A copolymer donor, PBQ9, which is based on difluoroquinoxaline A-unit with chlorine substitution on its alkyl-thiophene side chains instead of fluorine substitution. Chlorine substitution is less complicated and less costly than fluorine substitution.

The optimized binary polymer solar cell (PSC) using PBQ9 as the polymer donor and m-TEH as the acceptor showed a high power conversion efficiency of 18.81%, with a high fill factor of 80.59%, and the photovoltaic performance was insensitive to different batches of the polymer donor. The results indicate that PBQ9 is a high-performance polymer donor, and chlorine substitution is an effective strategy to improve the photovoltaic performance and reduce the cost of polymer donors.

Photo-CELIV and TPC measurements:were obtained by the all-in-one characterization platform, Paios.

arag, A., Feeney, T., Hossain, I. M., Schackmar, F., Fassl, P., Küster, K., Bäuerle, R., Ruiz-Preciado, M. A., Hentschel, M., Ritzer, D. B., Diercks, A., Li, Y., Nejand, B. A., Laufer, F., Singh, R., Starke, U., Paetzold, U. W.,

Adv. Energy Mater. 2023, 2203982.

https://doi.org/10.1002/aenm.202203982

This openaccess research article discusses the use of vacuum-based evaporation to deposit self-assembled monolayers (SAM-HTLs) based on carbazole functional groups with phosphonic acid anchoring groups in perovskite solar cells (PSCs). SAM-HTLs have previously been deposited exclusively via solution-based methods. The authors found that vacuum deposition preserves or even slightly improves the near lossless interfacial properties and is also found to improve perovskite wetting and fabrication yield on previously non-ideal materials. This research provides a new method for depositing SAM-HTLs and improving the versatility of these materials without sacrificing their beneficial properties.

Electrochemical Impedance Spectroscopy (EIS): EIS for the full device stack was conducted using Paios. The sweep frequency was from 1 Hz to 1 MHz with 70 mV amplitude and offset voltage equivalent to the device's VOC.

Li, Y., Wu, X., Zuo, G., Wang, Y., Liu, X., Ma, Y., Li, B., Zhu, X.-H., Wu, H., Qing, J., Hou, L., Cai, W.,

Adv. Funct. Mater. 2022, 2209728. https://doi.org/10.1002/adfm.202209728

This work presents a new electron transport layer (ETL) configuration for organic photovoltaics (OPVs) that comprises a solution-processed n-n organic heterojunction. The n-n heterojunction is constructed by stacking a narrowband n-type conjugated polymer layer and a wide-band n-type conjugated molecule layer to enhance electron transport and hole blocking, and boost power conversion efficiency (PCE) in OPV.

The new ETL configuration leads to substantial improvements in performance in three OPVs with different active layers due to the combination of selective carrier transport properties and reduced recombination, as well as the good film-forming quality of the new ETL configuration.

Device Characterization: The transient photovoltage (TPV) and photocurrent (TPC) measurements were characterized with PAIOS system (Fluxim) under open-circuit condition and a short-circuit condition, respectively.

Andrés-Felipe Castro-Méndez, Jamie P. Wooding, Selma Fairach, Carlo A. R. Perini, Emily K. McGuinness, Jacob N. Vagott, Ruipeng Li, Sanggyun Kim, Vivek Brahmatewari, Nicholas Dentice, Mark D. Losego, and Juan-Pablo Correa-Baena

ACS Energy Lett. 2023, 8, 1, 844–852

Publication Date: January 3, 2023

https://doi.org/10.1021/acsenergylett.2c02272

This study investigates the use of vapor phase infiltration (VPI) to improve the stability of organic charge transport layers, such as hole-selective spiro-OMeTAD in perovskite solar cells (PSCs) and other organic electronic devices.

By using X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and grazing incident wide-angle X-ray scattering (GIWAXS), the study identifies that infiltration of TiOx via VPI hinders the crystallization of the spiro-OMeTAD layer. The infiltrated PSCs retained over 80% of their original efficiency after an operando stability test of 200 hours at 75°C, double the efficiency retained by devices without infiltration. This study suggests VPI can be used to stabilize organic charge transport layers and prolong device lifetimes.

Device stability measurements were carried out by tracking the maximum power point (MPP) of the devices while keeping constant the temperature of the films (by Peltier pads) at 75 °C using the stability measurement platform Litos from Fluxim.

Carlo Andrea Riccardo Perini, Esteban Rojas-Gatjens, Magdalena Ravello, Andrés-Felipe Castro-Mendez, Juanita Hidalgo, Yu An, Sanggyun Kim, Barry Lai, Ruipeng Li, Carlos Silva-Acuña, and Juan-Pablo Correa-Baena

Adv. Mater. 2022, 34, 2204726

https://doi.org/10.1002/adma.202204726

This study investigates the impact of bulky-cation-modified interfaces on the stability of halide perovskite solar cells, which has not been extensively explored. The research demonstrates the thermal instability of these interface layers used in state-of-the-art solar cells and reveals changes in the chemical composition and structure of the films under thermal stress, which affects charge-carrier dynamics and device operation. The type of cation used for surface treatment also affects the extent of these changes, with long carbon chains providing more stable interfaces. The study emphasizes the importance of prolonged annealing of the treated interfaces to enable reliable reporting of performance and inform the selection of different bulky cations.

Device Characterization: The photovoltaic performance was evaluated using a Fluxim Litos Lite setup, equipped with a Wavelabs Sinus-70 AAA solar simulator with AM1.5 spectrum for excitation.

Aging tests were performed using a Fluxim Litos setup, using 1 Sun equivalent illumination with no UV-component, holding the substrates at 55 °C in a N2 atmosphere and using an MPP tracking algorithm. Every 12 h, a J–V scan in reverse and forward direction was automatically acquired.

CS Appl. Mater. Interfaces 2023, 15, 1, 1652–1660

https://doi.org/10.1021/acsami.2c17960

The presence of spontaneous orientation polarization (SOP) in the electron transport layer (ETL) of organic light-emitting devices (OLEDs), induced by the alignment of polar molecules with permanent dipole moments (PDMs), can reduce device efficiency by quenching excitons.

This work quantitatively examines SOP formation in the ETL, considering the impact of film processing conditions and treating the vapor-deposited film as a supercooled glass. The results provide a framework to predict the SOP formation efficiency for polar materials and blends, and in situ measurements reveal that SOP-induced exciton-polaron quenching can be mitigated through optimized processing conditions, leading to improved OLED efficiency.

Optical Outcoupling Calculations. Light outcoupling efficiencies (ηoc) for OLEDs of interest were calculated using the simulation results obtained from Setfos. During the simulation, an isotropic dipole orientation was assumed, and optical constants measured via spectroscopic ellipsometry were used. The IQE for each device is calculated by dividing its ηEQE by its corresponding ηOC.

Fan, XC., Wang, K., Shi, YZ. et al.

Nat. Photon. (2023). https://doi.org/10.1038/s41566-022-01106-8

Researchers developed a new ultrapure green emitter called DBTN-2 for use in organic light-emitting diode (OLED) displays, which has a highly efficient operation due to the introduction of multiple carbazole moieties resulting in a high density of triplet states and a fast rate of reverse intersystem crossing.

An OLED using DBTN-2 as an emitter demonstrated a high photoluminescence quantum yield, strong horizontal dipole orientation, and excellent external quantum efficiency of 35.2% with suppressed efficiency roll-off, meeting commercial requirements for a green OLED display.

The obtained PL intensity angle-dependent patterns were analysed using Setfos with refractive index n, extinction coefficient k values of SF3-TRZ at 520 nm (peak wavelength of DBTN-2) as basic information for simulation.

Carl Degitz , Markus Schmid, Falk May, Jochen Pfister, Armin Auch, Wolfgang Brütting, and Wolfgang Wenzel

Chem. Mater. 2023, 35, 1, 295–303

https://doi.org/10.1021/acs.chemmater.2c03177

Due to their thin amourphous structure, unique electrical properties, and the associated variety of possible applications, OLEDs can now be found in smartphones, TVs, laptops, and wearables. While already big steps have been made in optimizing and understanding the properties influencing the external quantum efficiency (EQE), there is still room for improvement, especially when it comes to finding design principles for new emitter complexes. One contributer to the EQE here is the molecular orientation of the emitter in a given host matrix.

In this work the researchers study the viability of using molecular modeling approaches in sampling these emitter orientations for a set of already published homoleptic Ir carbene emitters and a set of emitter materials synthesized at Merck KGaA, Darmstadt, Germany, comprising both homoleptic and heteroleptic Ir(ppy)3 derivatives.

They combined these simulations with different measurements for the orientation parameter and EQE, all performed with the same material stack under the same conditions. The research team observed a good agreement between simulation and experiment and found that the horizontal orientation of emitter molecules seems to be the main factor contributing to a higher EQE.

The Setfos Optics module was used to calculate the maximum possible EQE for emitter.

Yun Hu, Jing-song Huang, Paul Stavrinou, Donal D. C. Bradley

Proc. of SPIE Vol. 12314 123140O-2, 2023

Non-metallic mirror, such as semiconductor distributed Bragg reflectors (DBRs), has been widely integrated in the structure of optoelectronic devices.

However, constructing conductive DBR in organic optoelectronic device is still scarce, because of the incompatibility of high-temperature processes in the preparation of inorganic DBR.

Herein, it is confirmed that organic-oxide hybrid DBR can achieve high conductivity and light manipulation. When thermal evaporated material MoO3 is doped into organic material (1,1-bis[4-[N,N-di(p-tolyl)amino]phenyl]cyclohexane, TAPC), the conductivity of TAPC can be increased by ten thousand times with very small refractive index change.

It is shown that 8.5 pairs DBR at 460 nm has a reflectivity of about 95%, and the driving voltage is 8.2 V at the current density of 100 mA cm-2. Then, a transparent organic light-emitting diode with integrated bottom conductive DBR are fabricated to confirm the functionality of light regulation.

The results confirm that integrated optoelectronic devices with DBR as reflector can be achieved with low operating voltage.

The optical simulations of DBR and OLED devices were performed by using a commercially available SETFOS (Fluxim) software. The refractive index, extinction coefficient (k), photoluminescence (PL) spectrum of emissive layers and thickness of each layer were used as input parameters. Transfer matrix method (TMM) and Gaussian dipole distribution dipole emitter as source are used in simulation.

Li, Y., Wu, X., Zuo, G., Wang, Y., Liu, X., Ma, Y., Li, B., Zhu, X.-H., Wu, H., Qing, J., Hou, L., Cai, W.,

Adv. Funct. Mater. 2022, 2209728.

https://doi.org/10.1002/adfm.202209728

Efficient electron transport layer (ETL) based on a novel n-n heterojunction arrangement for organic photovoltaics (OPV).

The group of Whanzu Cai at the Guangzhou Key Laboratory of Vacuum Coating Technologies and New Energy Materials stacked an n-type conjugated film (PNDIT-F3N) with an n-type small molecule film (Phen-NaDPO) achieving a water-fall like alignment of electron transport energy levels. Devices with the n-n heterojunction ETL showed performance increase of up to 30% compared to control devices based on the isolated PNDIT-F3N or Phen-NaDPO ETLs.

They used the characterization tool Paios to investigate the charge extraction and recombination lifetimes with transient photocurrent (TPC) and transient photovoltage (TPV) measurements, respectively. Both extraction and recombination lifetimes improved by up to 100% for the devices with the n-n heterojunction compared to Phen-NaDPO alone.

van der Pol, T.P.A., Datta, K., Wienk, M.M. and Janssen,

R.A.J. (2022), Sol. RRL, 6: 2200872.

https://doi.org/10.1002/solr.202200872

A modeling approach is developed to correct outcoupled electroluminescence spectra in thin-film organic and perovskite solar cells. The approach takes into account self-absorption, cavity effects, and nonhomogeneous emission profile to yield intrinsic spectrum. The impact of these effects is studied for various device parameters to uncover trends and provide guidelines for a large set of devices.

Optical Modeling: The simulation procedure used here was based on Dyson et al. where the outcoupled spectrum is calculated using Setfos for a 1 nm emitter layer located in the active layer

Rahman, Md Abdur, Kim, Dong Kyu, Lee, Jong-Kwon and Byun, Ji Young.

Nanophotonics, vol. 11, no. 21, 2022, pp. 4855-4868.

https://doi.org/10.1515/nanoph-2022-0522

Structural colors with tunable properties have extensive applications in surface decoration, arts, absorbers, and optical filters.

CrON/Si3N4/Metal structures show promise for generating vivid structural colors with tunable properties and strong light absorption. Replacing top metallic layer with lossy dielectric prevents degradation from abrasiveness/oxidation. Theoretical and experimental data support these structures' durability and color generation via interference effect and absorption rate

The absorption of each layer and phase shift were calculated using Setfos.

Markus Regnat, Chang-Ki Moon, Sandra Jenatsch, Beat Ruhstaller, Kurt P. Pernstich,

Organic Electronics, Volume 108, 2022, 106570, ISSN 1566-1199,

https://doi.org/10.1016/j.orgel.2022.106570.

Highlights

• Increased driving voltage after prolonged operation.

• Radiant flux remained constant, so an electrical model is sufficient.

• Using multiple measurement methods, determine reliable model parameters.

• Sensitivity analysis reveals the origin of the increased driving voltage.

• Hole traps in TAPC are the main cause of the increased driving voltage.

Fluxim’s all-in-one measurement system, Paios, equipped with a temperature module and a photomultiplier from Hamamatsu (H11526 Series), was used to measure OLED characteristics.

Fluxim's Characterization Suite software (version 4.3) was used to analyze the obtained data, which included the Setfos-Paios-Integration feature for performing model parameter optimizations for fitting the measured data.

Steele, J.A., Braeckevelt, T., Prakasam, V. et al.

Nat Commun 13, 7513 (2022).

https://doi.org/10.1038/s41467-022-35255-9

The black perovskite phase of CsPbI3 is promising for optoelectronic applications; however, it is unstable under ambient conditions, transforming within minutes into an optically inactive yellow phase, a fact that has so far prevented its widespread adoption.

In this paper the research team present an effective strategy for embedding an interfacial microstructure (a PbI2 microgrid) into stable CsPbI3 perovskite thin films and devices, using a coarse photolithographic approach. The microgrid is shown to dramatically increase the long-term stability of black CsPbI3 thin films (beyond 2.5 years in a dry environment) by increasing the phase transition energy barrier (Eb) and limiting the spread of potential yellow phase formation to a single, isolated domain of the grid.

Using stabilized photodetectors, integration of a microgrid into normally unstable planar CsPbI3 perovskite devices is shown to be a simple and effective strategy toward stable ambient operation.

Paios was used to measure the rise and decay time and the capacitance of the devices. The pulsed J-V characteristics were measured from 2 V to −1 V with 50 ms, 1 ms, and 25 ms as the pulse length, rise time, and measurement time, respectively.

Weitz, P., Le Corre, V. M., Du, X., Forberich, K., Deibel, C., Brabec, C. J., Heumüller, T.,

Adv. Energy Mater. 2022, 2202564.

https://doi.org/10.1002/aenm.202202564

A method for organic solar cell (OSC) stability testing is presented that aims to provide more unique insight into the causes of degradation patterns of OSCs. The method involves using monochromatic light at high irradiation doses to accelerate isolated degradation mechanisms while monitoring the device with a series of in-situ steady-state and transient electrical measurements.

The experimental results are accompanied by drift-diffusion simulations to localize degradation pathways. PM6:Y6-based OSCs are tested, which are known to show a rather broad range of lifetimes as a function of device architecture, material batches, or degradation conditions. The experiments reveal a degradation mechanism that causes an increased trap-state density inside the PM6:Y6 layer.

The transient simulations suggest that these states are formed at or around the interface between the PM6:Y6 and the electron transport layer. Furthermore, the surprisingly dominant impact of the illuminating wavelength on the degradation pattern is evidenced.

Lastly, the degradation rate of the devices scales linearly with light intensity, making high intensity and spectrally selective degradation the most promising way to accelerate stability testing for the faster development of stable OSCs.

To localize a mechanism inside the device architecture, the commercial drift-diffusion module of the simulation software Setfos was used.

Cho, H., Joo, C. W., Kwon, B.-H., Kang, C., Choi, S., and Sin, J. W., ETRI Journal (2022), 1– 9.

doi.org/10.4218/etrij.2022-0236

Abstract

The optical properties of the materials composing organic light-emitting diodes (OLEDs) are considered when designing the optical structure of OLEDs. Optical design is related to the optical properties, such as the efficiency, emission spectra, and color coordinates of OLED devices because of the microcavity effect in top-emitting OLEDs.

In this study, the properties of top-emitting blue OLEDs were optimized by adjusting the thicknesses of the thin metal layer and capping layer (CPL). Deep blue emission was achieved in an OLED structure with a second cavity length, even when the transmittance of the thin metal layer was high.

The thin metal film thickness ranges applicable to OLEDs with a second microcavity structure are wide. Instead, the thickness of the thin metal layer determines the optimized thickness of the CPL for high efficiency.

A thinner metal layer means that higher efficiency can be obtained in OLED devices with a second microcavity structure. In addition, OLEDs with a thinner metal layer showed less color change as a function of the viewing angle.

Setfos was used to perform the optical simulations and to optimize the OLED stack design.

F. Didier, P. Alastuey, M. Tirado, M. Odorico, X. Deschanels, G. Toquer,

Thin Solid Films, Volume 764, 2023, 139614, ISSN 0040-6090,

doi.org/10.1016/j.tsf.2022.139614.

ABSTRACT

Carbon nanotubes (CNTs), deposited by electrophoretic deposition (EPD), are investigated as selective solar absorbers. First, various kinds of CNTs with different aspect ratios, are dispersed by ultrasound in an aqueous solution of pyrocatechol violet (PV). PV couples to the CNT’s outer walls via π-π stacking interactions and acts as a dispersing agent as well as a charging agent. PV adsorption isotherms on CNT combined with N2 physisorption isotherms are performed to optimize the CNT/PV ratio. In this way, Zeta potentials up to -40 mV are obtained for the dispersed CNTs, which are deposited on platinized silicon wafers by EPD, forming a film. The EPD kinetics are then investigated as a function of the applied electric field (in the 8–20 V cm− 1 range) and are explained through a Sarkar & Nicholson model type. X-ray reflectivity is performed to characterize the density around 1.3 g cm− 3 , and film cohesion is probed by nanoindentation coupled to atomic force microscopy images. The hemispherical reflectance of the samples is measured by spectrophotometers equipped with an integrating sphere, and following from spectra, the absorptance (α) and emittance (ԑ) are calculated. The selectivity of the deposits, based on α and ԑ values, is then discussed as a function of the applied electric field and the coating thickness.

Single-walled CNT deposits, at best, are found to have a solar absorptance of 0.91 and thermal emission of 0.05. Thermal annealing experiments reveal that the coatings could withstand up to 300 ◦C while sustaining selective properties and losing only 21% of the initial yield.

The researchers used Setfos to simulate the absorbed radiation and thermal emission of their films.

Hu, D., Tang, H., Karuthedath, S., Chen, Q., Chen, S., Khan, J. I., Liu, H., Yang, Q., Gorenflot, J., Petoukhoff, C. E., Duan, T., Lu, X., Laquai, F., Lu, S.,

Adv. Funct. Mater. 2022, 2211873.

doi.org/10.1002/adfm.202211873

Abstract

The commercial viability of all-small-molecule (ASM) organic solar cells (OSCs) requires high efficiency, long-term stability, and low-cost production.

However, satisfying all these factors at the same time remains highly challenging. Herein, a volatile solid additive, namely, 1,8-dichloronaphthalene (DCN) is demonstrated to simultaneously enhance the power conversion efficiency (PCE) and the storage, thermal as well as photo stabilities of oligothiophene ASM-OSCs with concise and low-cost syntheses.

The improved PCEs are mainly due to the DCN-induced morphology control with improved exciton dissociation and reduced non-geminate recombination. Notably, the PCE of 16.0% stands as the best value for oligothiophene ASM-OSCs and is among the top values for all types of binary ASM-OSCs. In addition, devices incorporating DCN have shown remarkable long-term stability, retaining over 90% of their initial PCE after dark storage aging of 3000 h and thermal or light stressing of 500 h.

The findings demonstrate that the volatile-solid-additive strategy can be a simple yet effective method of delivering highly efficient and stable oligothiophene ASM-OSCs with excellent commercial viability.

The 1D numerical drift-diffusion module of Setfos was used to simulate the O-ASM-OSCs device J–V characteristics.

Tasaki, S, Nishimura, K, Toyoshima, H, Masuda, T, Nakamura, M, Nakano, Y, et al.

J Soc Inf Display. 2022; 30( 5): 441– 451.

https://doi.org/10.1002/jsid.1127

The bilayer structure for an emitting layer (EML) was developed to improve performances of a fluorescence blue organic light emitting diode.

By functionally separating the EML into the charge recombination and the triplet–triplet fusion (TTF) zone, we successfully suppressed the quenching of triplet excitons by excess carriers to make more TTF efficient and the local degradation within the EML to make the lifetime longer.

In the bottom emission device with the bilayer EML, 12% of external quantum efficiency (EQE) and 450 h of LT95 were achieved. Furthermore, we achieved over 14% of EQE by optimizing the material combinations.

To estimate the emission ratio from BH1 and BH2, optical simulation by Setfos was conducted at 10 mA/cm2.20

Lee, H.-D., Jang, H. J., Baek, J. H., Kim, J.-J., Choi, H. C., Kim, J.-M., Lee, J. Y.

Adv. Optical Mater. 2022, 2202109.

doi.org/10.1002/adom.202202109

Abstract

Control of the molecular orientation is an effective approach to enhance the performance of organic light-emitting diodes. This study examines the molecular dipole orientation of hole transport materials depending on the deposition step and the consecutive effect on the transition dipole orientation of the emitting dopant.

In contrast to other reference materials, 4,4′,4′′-tris(carbazole-9-yl)triphenylamine (TCTA) shows a preferred orientation only in the continuously deposited films that is dependent on the film thickness. The horizontal dipole orientation ratio of the emitting dopant deposited on the TCTA is improved by the alignment of TCTA molecules.

The power efficiency of the device produced from the above materials is increased from 28.9 to 34.4 lm W−1 owing to the dual enhancement of the hole mobility of TCTA and the horizontal dipole orientation ratio of the emitting dopant. The molecular orientation of the charge transport layer contributes to charge transport in the layer and the molecular orientation of the adjacent emitting layer.

The optical simulation for determining the horizontal dipole ratio was performed using Setfos.

Yun-Jie Lin, Chia-Sheng Huang, Pei-Chung Tsai, Yu-Lun Hsiao, Cheng-Yu Chen, and Jwo-Huei Jou

ACS Applied Materials & Interfaces Article ASAP

DOI: 10.1021/acsami.2c18275

Abstract

Aluminum has been extensively used as a conductor material in numerous electronic devices, including solar cells, light-emitting diodes (LEDs), organic LEDs (OLEDs), and thin-film transistors. However, its spiking surface and easy electromigration have limited its performance.

To overcome this, a trace amount of nonprecious copper dopant has been proven effective in enhancing device reliability. Nevertheless, a comprehensive investigation regarding the effect of copper doping on the morphology at the aluminum conductor–organic interface is yet to be done. We had hence fabricated a series of green OLED devices to probe how copper doping affected the aluminum conductor, morphologically and electrically, and the corresponding device’s efficiency and lifetime performance.

Electrical simulation showing the effect of the cathode work function on the charge density distribution of the studied green OLED devices was performed using Setfos.

Tommaso Marcato, Frank Krumeich, and Chih-Jen Shih

ACS Nano 2022 16 (11), 18459-18471

DOI: 10.1021/acsnano.2c06600

Tuning the transition dipole moment (TDM) orientation in low-dimensional semiconductors is of fundamental and practical interest, as it enables high-efficiency nanophotonics and light-emitting diodes. However, despite recent progress in nanomaterials physics and chemistry, material systems that allow continuous tuning of the TDM orientation remain rare.

Here, combining k-space photoluminescence spectroscopy and multiscale modeling, we demonstrate that the TDM orientation in lead halide perovskite (LHP) nanoplatelet (NPL) solids is largely confinement-tunable through the NPL geometry that regulates the anisotropy of Bloch states, dielectric confinement, and exciton fine structure.

The experimental data were evaluated with the software Setfos provided by Fluxim.

The angle-dependent PL of the NPL film was characterized using the commercial instrument Phelos (Fluxim Inc.) equipped with a spectrometer, a linear polarizer, and a cylindrical macro extractor lens.

Luo, Y., Zhang, K., Ding, Z. et al.

Nat Commun 13, 6892 (2022).

https://doi.org/10.1038/s41467-022-34573-2

The harvesting of ‘hot’ triplet excitons through high-lying reverse intersystem crossing mechanism has emerged as a hot research issue in the field of organic light-emitting diodes.

However, if high-lying reverse intersystem crossing materials lack the capability to convert ‘cold’ T1 excitons into singlet ones, the actual maximum exciton utilization efficiency would generally deviate from 100%.

Herein, through comparative studies on two naphthalimide-based compounds CzNI and TPANI, we revealed that the ‘cold’ T1 excitons in high-lying reverse intersystem crossing materials can be utilized effectively through the triplet-triplet annihilation-mediated high-lying reverse intersystem crossing process if they possess certain triplet-triplet upconversion capability.

Angle-dependent photoluminescence was measured to obtain the horizontal dipole ratio (HDR, Θ//) of the light emission molecules in neat film state. p-polarized angle-dependent light emissions of films were measured by Fluxim. The HDR of thin films and light out-coupling efficiency of devices were then simulated by Setfos.

Liu, G., Li, Z., Hu, X. et al.

Nat. Photon. 16, 876–883 (2022).

https://doi.org/10.1038/s41566-022-01084-x

Organic light-emitting diodes (OLEDs) with thick carrier transport layers are desirable for high production yields of OLED-based displays and lighting; however, high operating voltages are inevitably introduced to thick OLEDs due to the low carrier mobilities of organics.

The associated Joule heating will also induce structural defects and lower operational stabilities. Here, the researchers demonstrate highly efficient and stable OLEDs with thicknesses of over 1 μm and low operating voltages.

The researchers used the advanced simulation software Setfos.

Hu, Y.X., Miao, J., Hua, T. et al.

Nat. Photon. 16, 803–810 (2022).

https://doi.org/10.1038/s41566-022-01083-y

Organic light emitters based on multiresonance-induced thermally activated delayed fluorescent materials have great potential for realizing efficient, narrowband organic light-emitting diodes (OLEDs).

However, at high brightness operation, efficiency roll-off attributed to the slow reverse intersystem crossing (RISC) process hinders the use of multiresonance-induced thermally activated delayed fluorescent materials in practical applications. In this paper, the researchers report a heavy-atom incorporating emitter, BNSeSe, which is based on a selenium-integrated boron–nitrogen skeleton and exhibits 100% photoluminescence quantum yield and a high RISC rate (kRISC) of 2.0 × 106 s−1.

The corresponding green OLEDs exhibit excellent external quantum efficiencies of up to 36.8% and ultra-low roll-off character at high brightnesses (with very small roll-off values of 2.8% and 14.9% at 1,000 cd m−2 and 10,000 cd m−2, respectively).

The optical simulation of OLED devices was performed using Setfos. The input parameters include refractive index value, extinction coefficient, thickness of each layer values (all measured by ellipsometry), as well as photoluminescence spectrum of the emitting layer.

Abhijeet Choudhury, Mangey Ram Nagar, Luke The, Yun-Jie Lin, Yu-Hong Liang, Sun-Zen Chen, Jwo-Huei Jou,

Organic Electronics, Volume 111, 2022, 106668, ISSN 1566-1199,

https://doi.org/10.1016/j.orgel.2022.106668

High-efficiency organic light-emitting diodes (LEDs) can be achieved by employing efficiency-effective materials coupling with suitable device architectures.

Among them, there have been numerous hole-injection and -transport materials reported, but having issues of high-cost, solution-process feasibility, and toxic solvent involvement. In this paper the researchers demonstrate a low-cost solution-processable nanocrystalline copper iodide (CuI) as a hole-injection and -transport material for the fabrication of high-efficiency organic LED.

Outcoupling efficiency is a crucial factor that help in the OLEDs efficiency enhancement. To measure the outcoupling efficiency of OLEDs, which has amorphous CuI and nanocrystalline CuI as HIL/HTL, optical simulation was performed using SETFOS. For the optical simulation, optical parameter, i.e. refractive index, of all functional layers were provided in the software package.

M. Diethelm, A. Devižis, W.-H. Hu, T. Zhang, R. Furrer, C. Vael, S. Jenatsch, F. Nüesch, R. Hany

Adv. Funct. Mater. 2022, 32, 2203643. https://doi.org/10.1002/adfm.202203643

This research investigates the impact of electron and hole traps on the performance and lifespan of polymer light-emitting electrochemical cells (PLECs). The study aims to identify and analyze the role of these traps in PLECs, drawing parallels with their known impact on polymer light-emitting diodes (PLEDs).

The researchers fabricated PLECs using a super yellow (SY) polymer as the emitting material and employed various experimental techniques, including electrical driving and breaks, light irradiation, and long-term absorption and capacitance measurements. Optical and electrical simulations using Setfos provided further insights into device behavior.

The findings reveal that electron traps in PLECs share similar characteristics with those in PLEDs, suggesting a common origin in the semiconducting polymer. Notably, the study identifies two types of hole traps in PLECs: one type present in the intrinsic region, mirroring PLED behavior, and another type forming at the interface of the intrinsic and p-doped regions, specific to the PLEC architecture.

This research highlights the significant role of charge traps in limiting PLEC performance and longevity. The findings emphasize the need for strategies beyond conventional approaches to enhance PLEC stability, urging a focus on addressing the fundamental limitations posed by charge traps within the light-emitting polymer itself.

How Setfos Was Used

Setfos was used to perform optical and electrical simulations of the PLEC devices to better understand their properties, such as luminance versus emitter position.

How Paios Was Used

Paios was used to perform several different types of measurements on the PLEC devices:

Impedance measurements: Specifically, impedance measurements at 0 V with an alternating 70 mV signal were taken to determine the capacitance transients of the devices.

Current and light intensity transient measurements: The Paios measurement system was also used to measure how the current and light intensity changed over time. The light intensity was measured by using a photodiode to measure the photovoltage, and the relationship between the measured photovoltage and the corresponding radiance/luminance is explained in a different source.

How Phelos Was Used

Phelos was used to take angular-dependent electroluminescence (EL) measurements of the PLEC devices.

Andrés-Felipe Castro-Méndez, Carlo A. R. Perini, Juanita Hidalgo, Daniel Ranke, Jacob N. Vagott, Yu An, Barry Lai, Yanqi Luo, Ruipeng Li, and Juan-Pablo Correa-Baena

ACS Applied Materials & Interfaces Article ASAP

DOI: 10.1021/acsami.2c02036

Thermal evaporation is a promising deposition technique to scale up perovskite solar cells (PSCs) to large areas, but the lack of understanding of the mechanisms that lead to high quality evaporated methylammonium lead triiodide (MAPbI3) films gives rise to devices with efficiencies lower than those obtained by spin coating.

In this paper the researchers investigate the role of Sr and Ca additives to CsFA-PbI solar cells on performance.

Litos Lite was used to perform JV scan under 1 sun illumination.

Ahmer A.B. Baloch, Omar Albadwawi, Badreyya AlShehhi, Vivian Alberts,

Energy Reports, Volume 8, Supplement 16, 2022,

ISSN 2352-4847,

https://doi.org/10.1016/j.egyr.2022.10.215

What is the worldwide performance of silicon/perovskite solar cells compared to the respective single-junctions?

That is the question that the group of Vivian Alberts from the Research and Development Center of the Dubai Electricity and Water Authority answered by simulating the energy yield and cell temperature depending on the geographical location.

Considering a perovskite solar cell with a bandgap of 1.7eV, tandem cells generate on average 26.7% more energy than silicon solar cells, while dissipating less heat thanks to the higher electrical efficiency. The optimal latitude for tandem performance in the 45◦N to 45◦S range.

With the simulation software Setfos from Fluxim AG they could estimate the theoretical efficiency limit of the tandem device under standard testing conditions (STC) using detailed balance analysis.

Sun, Q., Tuo, B., Ren, Z., Xue, T., Zhang, Y., Ma, J., Li, P., Song, Y.

Adv. Funct. Mater. 2022, 2208885.

doi.org/10.1002/adfm.202208885

Yanlin Song and colleagues at the Chinese Academy of Sciences embedded TU as a dopant in PbI2 and they used it as interface treatment at the SnO2/perovskite interface. Devices with either of the two treatments presented larger grains, and lower defect concentration. The treatment released tensile stress in the #perovskite by reducing the interface lattice mismatch at the SnO2/perovskite heterojunction. The champion solar cell reached a PCE of 24.4% and retained 80% of the initial efficiency after 120 hours of stressing at 60°C in N2.

Transient photocurrent (TPC), transient photovoltage (TPV), and space-charge limited current (SCLC) were performed with Paios from FLUXiM AG. These experiments confirmed the improvement in charge carrier transport and reduction in recombination thanks to the reduced defect concentration.

Fan, B., Gao, W., Wu, X. et al.

Nature Communications 13, 5946 (2022).

doi.org/10.1038/s41467-022-33754-3

Power conversion efficiency and long-term stability are two critical metrics for evaluating the commercial potential of organic photovoltaics.

Although the field has witnessed a rapid progress of efficiency towards 19%, the intrinsic trade-off between efficiency and stability is still a challenging issue for bulk-heterojunction cells due to the very delicate crystallization dynamics of organic species. Herein, the research team from the City University of Hon Kong developed a class of non-fullerene acceptors with varied side groups as an alternative to aliphatic chains.

Delay-time charge extraction by linearly increasing voltage (CELIV) was measured on the all-in-one platform of Paios (FluximAG). A light pulse with duration of 50 μs generated from an 810 nm LED lamp (light intensity 100%) was applied prior to a voltage ramp of 1 V μs–1.

The delay time between light pulse and voltage ramp was varied from 0.2 to 10 μs. During the delay time, the open circuit was kept by applying the transient photovoltage signal to ensure no current is flowing.

Aurimas Vyšniauskas, Simon Keegan, Kasparas Rakstys, Tobias Seewald, Vytautas Getautis, Lukas Schmidt-Mende, Azhar Fakharuddin

Organic Electronics, Volume 111, 2022, 106655, ISSN 1566-1199

doi.org/10.1016/j.orgel.2022.106655

Perovskite light emitting diodes (PeLEDs) have emerged as promising candidates for applications requiring visible and near-infrared emission.

In this work, the researchers demonstrate the importance of compositional tuning using three different 2D cations namely phenylethylammonium (PEA), its monofluorinated analogue FPEA and a custom-made bulkier cation BPEA containing an extra phenyl ring.

Their results show that the tuning of the ratio between 2D cation and the [PbX6]4- provides a trade-off between electrical transport in the device and the emission properties of the emissive layer.

Generally, a large excess of cations is required to enhance the external quantum efficiency (EQE) of PeLEDs. Among the various cations, FPEA leads to PeLEDs with the highest EQE up to 7.7%, while BPEA resulted in the smallest EQE.

External quantum efficiencies (EQEs), current density-voltage-luminance dependencies, electroluminescence spectra and lifetimes were measured using Fluxim’s Phelos angular luminescence spectrometer. EQE and lifetime measurements were performed at 1 mA current. EQE measurements were performed at a given current density to minimize time for characterisation and degradation of the device. Absorbance of the perovskite films were measured using Agilent Cary 5000 UV-Vis-NIR spectrometer.

Yutaka Noguchi, Kaito Ninomiya, and Katsuya Sato

The Journal of Physical Chemistry C Article ASAP

DOI: 10.1021/acs.jpcc.2c05871

Understanding the charge distributions in the vicinity of the emission layer (EML) of an organic light-emitting diode (OLED) is crucial for improving device performance.

In this paper the researchers from Meiji University, Japan propose a simple but powerful technique for investigating the correlations between the dynamics of charge carriers and excitons. This technique (DCM-PL) is based on displacement current measurement (DCM) with simultaneous observation of the photoluminescence (PL) intensity.

By applying this technique to metal−insulator−semiconductor (MIS) devices incorporating a partial stack of a tris(2-phenylpyridine) iridium (III) [Ir(ppy)3]-based organic light-emitting diode (OLED), they were able to investigate the hole accumulation behavior and the corresponding PL losses due to exciton-polaron quenching (EPQ).

Remarkably, the DCM-PL characteristics revealed that the polarity of the host material in the emission layer modifies the chargecarrier dynamics and EPQ properties. The results contribute to the optimization of OLED device performance, since EPQ is a key process involved in efficiency roll-off and device degradation.

The DCM curves for the CBP and TPBi host devices, respectively, were calculated using Setfos 5.2.

Liu, G., Li, Z., Hu, X. et al.

Nature Photonics. 24 Oct. 2022

doi.org/10.1038/s41566-022-01084-x

Organic light-emitting diodes (OLEDs) with thick carrier transport layers are desirable for high production yields of OLED-based displays and lighting; however, high operating voltages are inevitably introduced to thick OLEDs due to the low carrier mobilities of organics.

The associated Joule heating will also induce structural defects and lower operational stabilities. Here the research team led by demonstrate highly efficient and stable OLEDs with thicknesses of over 1 μm and low operating voltages.

The p-polarized emitted light fittings were performed with the Setfos software38 to model a quartz/emitting layer (20 nm)/air based on their corresponding refractive index and emission wavelength.

Kunsik An, Chaewon Kim, Kwan Hyun Cho, Seunghwan Bae, Bo Kyung Cha, Kyung-Tae Kang,

Organic Electronics, Volume 100, 2022, 106384

doi.org/10.1016/j.orgel.2021.106384

An X-ray detector system was fabricated with an organic small molecule photodetector and a terbium-doped gadolinium oxysulfide (Gd2O2S:Tb) scintillating screen. Though the microsphere cluster structure of the Gd2O2S film had advantage in low material cost, wavelength matching to the proper photodetector is challenging due to its scintillating performance property in the relatively narrow emission spectrum range.

This work, including the spectral tuning using the strong microcavity effect and X-ray detection for medical applications, will provide new insights for the further development of OPDs.

The optical calculation of the absorption spectra was carried out using SETFOS. The optical constants n (refractive index) and k (absorption index) were obtained from the software.

Yiting Jiang, Zhengli Lu, Shengli Zou, Huagui Lai, Zhihao Zhang, Jincheng Luo, Yuanfang Huang, Rui He, Jialun Jin, Zongjin Yi, Yi Luo, Wenwu Wang, Changlei Wang, Xia Hao, Cong Chen, Xin Wang, Ye Wang, Shengqiang Ren, Tingting Shi, Fan Fu, Dewei Zhao,

Nano Energy, Volume 103, Part A, 2022, 107818, ISSN 2211-2855,

https://doi.org/10.1016/j.nanoen.2022.107818.

Ethylenediammonium halide salts (i.e., EDAI2 and EDABr2) are good candidates to passivate Sn oxidation and deep traps in lead-free Sn-based Perovskite.

The group of Dewei Zhao at the Institute of New Energy and Low-Carbon Technology in Sichuan university recently discovered that EDABr2-modified perovskite devices could achieve 14.23% efficiency and retain 95% of the performance after 110 hours at operating conditions.

By performing transient photocurrent (TPC) and transient photovoltage (TPV) measurements with the Paios tool from Fluxim AG, they observed a TPC lifetime improvement from 1.29 us to 0.74 us and TPV lifetime from 5.9 us to 37.83 us, confirming the improved charge transport and charge recombination lifetimes.

Sun, G., Jiang, X., Li, X. et al.

Nat Commun 13, 5267 (2022).

https://doi.org/10.1038/s41467-022-32964-z

Polymeric small molecule acceptors (PSMAs) are narrow bandgap small-molecule acceptors (SMAs) copolymerized with a π-bridge linking unit (linker). A power conversion efficiency of 17.24% was reached recently at the Beijing National Laboratory of Molecular Sciences by testing three PY-IT derivatives. PG-IT2F was the champion polymer with lower recombination and improved charge transport.

And FLUXiM AG tools are supporting their research. With Paios they performed light-dependent transient photovoltage (TPV) measurements and estimated a charge lifetime of 0.769 us on PG-IT2F-based solar cells compared to 0.436 us for the reference PY-IT PVs.

Sandheep Ravishankar, Zhifa Liu, Uwe Rau, and Thomas Kirchartz

PRX Energy 1, 013003 – Published 7 April 2022

Capacitance methods, such as capacitance-voltage-frequency measurements, Mott-Schottky analysis, and thermal-admittance spectroscopy measurements, are powerful tools to obtain important parameters of the solar cell, such as doping and defect densities, built-in voltages, and activation energies.

However, the validity of these analyses assumes that the capacitance response originates solely from the absorber layer.

Here, the authors demonstrate that this assumption is not valid for perovskite solar cells, since the thin and low-mobility selective-contact layers significantly contribute to the measured capacitance. Using a combination of drift-diffusion simulations and analytical modeling, they develop guidelines for the measurement of doping and defect densities, built-in voltages, and activation energies from these capacitance methods. These guidelines can be applied to any photovoltaic technology that incorporates low-conductivity charge-transport layers in addition to the absorber layer.

Simulation with ions was performed using Setfos.

Han-un Park, Seong Keun Kim, Raju Lampande, Jang Hyuk Kwon

Organic Electronics, Volume 105, 2022, 106496, ISSN 1566-1199,

https://doi.org/10.1016/j.orgel.2022.106496.

Here, the researchers report surface plasmon (SP) loss improved top-emitting organic light emitting diodes (TEOLEDs) by applying their unique cathode unit structure. Generally, the TEOLED has high optical loss portion of SP mode compared to the bottom emitting OLED and it causes low out-coupling efficiency in the TEOLED. Commonly used TEOLED structure uses Ag:Mg (10:1, 22 nm) cathode with high refractive index single capping layer, which has high optical loss portion of SP mode. To reduce SP mode loss in the TEOLED, we applied thin Ag:Mg (10:1, 12 nm) cathode with multi-capping layer. Our cathode unit reduces 55% of SP loss and enhances about 20% efficiency.

Their approach to enhance out-coupling efficiency will be useful to make high efficiency TEOLEDs.

The optical simulations of TEOLEDs were performed using Setfos. The refractive index, extinction coefficient, photoluminescence spectrum of emissive layer and thickness of each layer were used as input parameters.

Guanding Mei , Weigao Wang, Dan Wu, Philip Anthony Surman, Kai Wang , Wallace C. H. Choy , Xiaochuan Yang, Wenwei Xu, and Xiao Wei Sun

IEEE PHOTONICS JOURNAL, VOL. 14, NO. 2, APRIL 2022

https://ieeexplore.ieee.org/document/9735367

Full-color display is a primary challenge for the commercialization of quantum dots (QDs). In this study, we utilize the spectral narrowing phenomenon of microcavities to fabricate the red, green and blue quantum dot light-emitting diodes (QLEDs) with a single QD layer.

Because QD can be approximated as a point dipole source, the optical simulations are based on the dipole model and were performed by Setfos.

Maki Hiraoka, Nobuyuki Ishida, Akio Matsushita, Ryusuke Uchida, Takeyuki Sekimoto, Teruaki Yamamoto, Taisuke Matsui, Yukihiro Kaneko, Kenjiro Miyano, Masatoshi Yanagida, and Yasuhiro Shirai

CS Appl. Energy Mater. 2022, 5, 4, 4232–4239

doi/10.1021/acsaem.1c03747

Kelvin probe force microscopy has been employed to monitor the cross-sectional potential profile in lead-halide perovskite photovoltaic cells. From systematic investigations on many devices under varying bias voltage and light illumination conditions, we are able to deduce quantitative profile features with low noise that allows us to compare the local electronic properties in the working devices against numerical calculations.

The research team applied this technique to devices before and after degradation. Through the profile change before and after, we located the degraded components and inferred the source of the loss of the performance.

Setfos was used to simulate the photovoltaic actions of the device.

Palepu Ashok, Jay Chandra Dhar

2022 International Conference for Advancement in Technology (ICONAT), 2022, pp. 1-6,

doi: 10.1109/ICONAT53423.2022.9725852.

Here the researchers designed an HTL free photo detector with ZnO as an electron transport layer (ETL) fabricated using RF sputtering and the perovskite material CH3NH3PbI3 as a light absorbing material deposited using two-step spin coating method.

The performance of the device is modelled by using SETFOS software with the impedance spectroscopy technique by changing different metal electrodes like, Ag, Au, Pd and Pt. Among all, the Pt electrode showed high current density (18.6914 mA/cm^2), high fill factor (0.558) and maximum power conversion efficiency (18.5%).

Dhruba B. Khadka, Yasuhiro Shirai, Masatoshi Yanagida, Terumasa Tadano, Kenjiro Miyano

Adv. Energy Mater. 2022, 2202029

doi.org/10.1002/aenm.202202029

Surface treatment with fluoroarene derivatives increases the efficiency and long-term stability of MA/Br-free #perovskites.

Recently, researchers at the National Institute for Materials Science reached a certified 21% efficiency on a 1cm^2 #perovskite solar cell that does not contain the thermally unstable methylammonium (MA) or Br. This was possible through surface passivation based on fluoroarene derivatives. The passivated device retains 80% of the performance after 300h at 60-65% of humidity and about 90% after 500h at 65°C.

With #Paios from FLUXiM AG they measured lower defect density and slower photovoltage decay by means of capacitance-voltage (CV) and transient photovoltage (TPV), respectively, which confirms defects passivation. Paios is an all-in-one instrument that allows full optoelectrical characterization of solar cells and LEDs.

Qiwei Xu, I. Teng Cheong, Hanfa Song, Vien Van, Jonathan G. C. Veinot, and Xihua Wang

ACS Photonics 2022, 9, 8, 2792–2801

doi/pdf/10.1021/acsphotonics.2c00587

Integrating lead sulfide (PbS) colloidal quantum dots (CQDs) with crystalline silicon (c-Si) has been proven to be an effective strategy in extending the sensitivity of Si-based photodetectors into infrared regime. Here, the research team demonstrate the successful integration of PbS CQD inks with Si and construct a highly efficient heterojunction infrared photodiode operating in the range from 800 up to 1500 nm.

Summary points:

∙PbS CQD on Si to increase sensitivity of Si to IR

∙CQD:Si photodetector operating from 800 to 1500 nm

∙Layer of p-type QD enhances built-in electric field

∙EQE of 44% at 1280nm and 2V reverse bias - stable for more than 600 h

∙Photoresponse lower than 4μs without tails indicate low trap density

Lead sulfide (PbS) colloidal quantum dots (CQD) enable Si photodector sensitivity in the near infrared (NIR) in the range from 800 to 1500 nm.

The group of Xihua Wang at the University of Alberta achieved this result by spin-coating PbS CQD to form a CQD:Si heterojunction photodetector. The addition of a p-type CQD buffer layer at the CQD:Si interface enhanced the built-in electric field and improved the charge extraction. With transient photocurrent (TPC) and photovoltage (TPV) they measured a photoresponse lower than 4μs demonstrating low trap density at the CQD:Si interface.

TPC and TPV measurements were possible thanks to the all-in-one characterization platform PAIOS from Fluxim AG.

Leemans, J., Pejović, V., Georgitzikis, E., Minjauw, M., Siddik, A. B., Deng, Y.-H., Kuang, Y., Roelkens, G., Detavernier, C., Lieberman, I., Malinowski, P. E., Cheyns, D., Hens, Z.

Adv. Sci. 2022, 9, 2200844.

doi.org/10.1002/advs.202200844

QD-photodetectors are cost-effective, have small pixel pitch, and high spectral tunability, but they generally rely on restricted elements such as Pb and Hg. The team at Ghent University and imec fabricated high-efficiency photodetectors with non-restricted In(As,P) QDs deposited by spin-coating. These devices exhibit the best internal quantum efficiencies at the QD band gap of 46±5% and are sensitive to SWIR light up to 1400 nm.

Paios was used to characterize the photodetectors both in DC and transient modes. Thanks to all co-authors for your trust in our products.

Xiaoyu Gu, Xue Lai, Yuniu Zhang, Teng Wang, Wen Liang Tan, Christopher R. McNeill, Qian Liu, Prashant Sonar, Feng He, Wenhui Li, Chengwei Shan, and Aung Ko Ko Kyaw

Adv. Sci. 2022, 2200445

doi/pdf/10.1002/advs.202200445

∙TA vs TA-free to optimize Voc loss in OSC (CV, EIS

∙20.6% small area, 16.5% large area

∙high Voc. Champion has Voc loss of 0.001V (almost perfect ICL)

∙Eg 1.4 and 1.9

∙700h stability in N2

1mV difference between the Voc of an organic-perovskite tandem solar cell and the sum of the individual sub-cells. Almost perfect charge transport.

The tandem is a combination of an organic PM6:Y6 (1.49eV) and an all-inorganic perovskite (1.92eV). The remarkable result was obtained by the group of Aung Ko Ko Kyaw at the Gunagdong University by optimizing the electron transport of the perovskite subcell and the interconnection layer (ICL) between the subcells.

Investigation of thermal annealing (TA) treatments effect revealed that TA creates a barrier at the ICL (electrode/PFN-Br interface), hence it must be avoided for efficient charge transport between the subcells.

This result was obtained by carrying out capacitance and impedance measurements with the all-in-one platform Paios from Fluxim AG.

Rossa Mac Ciarnáin*, Hin Wai Mo, Kaori Nagayoshi, Hiroshi Fujimoto, Kentaro Harada, Robert Gehlhaar, Tung Huei Ke, Paul Heremans & Chihaya Adachi*

Advanced Materials (2022)

https://onlinelibrary.wiley.com/doi/full/10.1002/adma.202201409

An accessible method based on a single emission spectrum that enables emission zone measurements with sub-second time resolution in an organic light-emitting diode (OLEDs) is shown. A procedure is introduced to study and control the emission zone of an LED system and correlate it with device performance. A thermally activated delayed fluorescence organic LED emission zone is experimentally measured over all luminescing current densities while varying the device structure and while aging.

Emmanuel O. Afolayan , Ibrahim Dursun , Chao Lang, Evgeny Pakhomenko ,Marina Kondakova, Michael Boroson , Michael Hickner, Russell J. Holmes , and Noel C. Giebink

Physical Review Applied 17, LO51002 (2022)

DOI: 10.1103/PhysRevApplied.17.L051002

Spontaneous orientational polarization (SOP) in the electron-transport layer (ETL) of OLEDs is increasingly recognized as a key factor influencing their performance. The authors shows that SOP is dramatically reduced in the common electron-transport material 2,2,2- (1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) by coevaporating it together with medium-density polyethylene. Eliminating SOP from the ETL of blue fluorescent OLEDs reduces their operating voltage by 0.5 V, increases their external quantum efficiency (EQE) by 30%, and leads to a threefold increase in device lifetime.

Thomas Webb, Wei Zhang et al

Adv. Energy Mater. 2022, 2200666

DOI: 10.1002/aenm.202200666

Over the last decade spiro-OMeTAD has remained the hole transporting layer (HTL) of choice for producing high efficiency perovskite solar cells (PSCs).

However, PSCs incorporating spiro-OMeTAD suffer significantly from dopant induced instability and non-ideal band alignments. Herein, a new approach is presented for tackling these issues using the functionality of organometallocenes to bind to Li+ dopant ions, rendering them immobile and reducing their impact on the degradation of PSCs.

The electrical impedance spectra were recorded on the all-in-one Paios characterization platform

Jianhua Jing, Sheng Dong, Kai Zhang,* Zhisheng Zhou, Qifan Xue, Yu Song, Zurong Du, Minrun Ren, and Fei Huang

Adv. Energy Mater. 2022, 2200453

DOI: 10.1002/aenm.202200453

Semitransparent organic solar cells (ST-OSCs) have promising prospects for building or vehicle integrated solar energy harvesting with energy generation and see-through function. How to achieve both an adequate average visible transmittance (AVT) and high-power conversion efficiency (PCE) is always the key issue.

Herein, a simple but effective strategy for constructing high performance ST-OSCs by introducing a small molecule [2-(9-H-Carbazol9-yl) ethyl] phosphonic acid (2PACz) into a low-donor content active layer is reported.

The TPV technique using Paios was based on monitoring the photovoltage decay upon a small optical perturbation during different constant bias light-intensity. As were dark C–V measurements.

Yuliar Firdaus, Thomas D. Anthopoulos, et al

2022 Adv. Nat. Sci: Nanosci. Nanotechnol. 13 025001

DOI: 10.1088/2043-6262/ac6c23

The power conversion efficiency of nonfullerene-based organic solar cells (OSCs) has recently exceeded 18%, thanks to the constant effort to identify the key properties governing the OSCs performance and development of better photovoltaic materials.

With its superior properties, low-bandgap Y6 and its derivatives have emerged as one of the most popular nonfullerene acceptors (NFAs) for OSCs. In this work, the researchers compare two wide-bandgap Y6 derivatives with different end-groups, and their distinct device performance is correlated with their charge transport and recombination properties.

Light-intensity dependence measurements (J-V, TPV, CE, TPC) were performed with Paios.

Kanyaporn Thubthong, Psisit Kumnorkaew, Anusit Kaewprajak, Khathawut Lohawet, Wiyada Saennawa, Vinich Promarak, Yingyot Infahsaeng,

Thin Solid Films, Volume 741, 2022, 139012,

doi.org/10.1016/j.tsf.2021.139012

In this study, the researchers introduce a bis (perylene diimide) derivative as a buffer layer of the electron transporting layer by the rapid convective deposition technique. The maximum power conversion efficiency of 13.38% with less hysteresis is achieved from the device with perylene diimide as the electron transporting layer. Further, we found that the performance of the perylene-based device is enhanced due to the lower transporting resistance and the increasing electron mobilities. These results suggest that the perylene diimide derivatives can play a crucial influence in the charge transporting enhancement of perovskite solar cells.

Paios was used to perform impedance and equivalent circuit fitting to demonstrate lower charge transport resistance.

Wei-Hsu Hu, Camilla Vael, Matthias Diethelm, Karen Strassel, Surendra B. Anantharaman, Abdessalem Aribia, Marco Cremona, Sandra Jenatsch, Frank Nüesch, and Roland Hany

Adv. Optical Mater. 2022, 2200695

DOI: 10.1002/adom.202200695

Organic upconversion devices (OUCs) consist of an organic infrared photodetector and an organic visible light-emitting diode (OLED), connected in series. OUCs convert photons from the infrared to the visible and are of use in applications such as process control or imaging.

Many applications require a fast OUC response speed, namely the ability to accurately detect in the visible a rapidly changing infrared signal.

Here, high image-contrast, narrowband OUCs are reported that convert near-infrared (NIR) light at 980 and 976 nm with a full-width at half maximum of 130 nm into visible light. Transient photocurrent measurements show that the response speed decreases when lowering the NIR light intensity. This is contrary to conventional organic photodetectors that show the opposite speed-versus-light trend.

It is further found that the response speed increases (when using a phosphorescent OLED) or decreases (for a fluorescent OLED) when increasing the driving voltage.

To understand these surprising results, an analysis by numerical simulation is conducted. Results show that the response speed behavior is primarily determined by the electron mobility in the OLED. It is proposed that the low electron drift velocity in the emitter layer sets a fundamental limit to the response speed of OUCs.

Optical and electrical simulations were performed with Setfos 5.2

Camilla Vael, Sandra Jenatsch, Simon Züfle, Frank Nüesch, and Beat Ruhstaller

Journal of Applied Physics 131, 205702 (2022)

doi.org/10.1063/5.0088426

Simplified physical models are insufficient to describe the transient current after thermal stimulation in organic semiconductors. This is a recent finding from the group of Beat Ruhstaller. Drift-diffusion simulations obtained with the simulation software Setfos revealed the shortcomings of the physical models.

Simulations modeling is more powerful than analytical approaches for the interpretation of experimental data by accounting for non-ideal properties like exciton splitting and non-homogenous trap densities.

Matthias Diethelm, Michael Bauer, Wei-Hsu Hu, Camilla Vael, Sandra Jenatsch

Adv. Funct. Mater. 2022, 2106185

DOI: 10.1002/adfm.202106185

In this paper the researchers investigate electron trap dynamics in SY PLEDs and discover a recovery feature of the traps during stress interruption. Formation of this trap states takes several minutes. Same behaviour was found for P3HT, MEH-PPV.

The optical and electrical characterization tool Paios was used to stress the PLED and investigate trap dynamics with/without light bias. Additionally TEL experiments show an overshoot if the break time between stressing is extended. Transient Setfos simulations for fast trap dynamics and steady-state voltage depending on Nt.

Soobin Sim, Jinha Ryu, Dae Hyun Ahn, Hyunsu Cho, Chan-mo Kang, Jin-Wook Shin, Chul Woong Joo, Gi Heon Kim, Chun-Won Byun, Nam Sung Cho, Hyoc Min Youn, Young Jae An, Jin Sun Kim, Hanyung Jung, and Hyunkoo Lee,

Opt. Express 30, 24155-24165 (2022)

doi.org/10.1364/OE.463095

Herein, the color gamut change by optical crosstalk between sub-pixels in high-resolution full-color organic light-emitting diode (OLED) microdisplays was numerically investigated. The color gamut of the OLED microdisplay decreased dramatically as the pixel density of the panel increased from 100 pixels per inch (PPI) to 3000 PPI.

Both Setfos and Laoss were used by the research team to perform optical simulations. To conduct the optical crosstalk simulation, the EL spectra was simulated using Setfos and the simulated EL spectra were well matched with the measured EL spectra. The transmittances of the R and G CFs provided by Laoss.

Tom P. A. van der Pol, Kunal Datta, Martijn M. Wienk, and René A. J. Janssen

Adv. Optical Mater. 2022, 2102557

doi.org/10.1002/adom.202102557

Photoluminescence (PL) helps you determine material properties and dynamic effects in #perovskite devices. But it is not easy to interpret PL spectra of #perovskites and get to the intrinsic material properties. This work is showing you how to do it.

The group of Prof. Rene Janssen at the Eindhoven University of Technology developed an optical model to quantify the intrinsic PL of a perovskite film and determine the influence of the extrinsic factors on the measured PL. The model is based on film thickness, refractive index, extinction coefficient, and carrier diffusion length as input parameters. The authors concluded that the largest mismatch between intrinsic and measured PL is observed for materials with a long diffusion length (>0.5um) and a layer thickness of >300nm.

The simulation software Setfos was instrumental in calculating an accurate emission spectrum to quantify the intrinsic PL for the perovskite. The simulation uses the real nk spectra of the materials and layer thickness as an input, which is the key to resolving the optical system.

The description you find in this paper can be used as a protocol to analyze your PL data on perovskite films.

Hurriyet Yuce, Diana LaFollette, Mustafa M. Demir, Carlo A.R. Perini, Juan-Pablo Correa- Baena

Sol. RRL 2100999.

doi.org/10.1002/solr.202100999

In the article the researchers investigate the crystal formation of co-evaporated MAI -PbI2 films at different temperature on the Perovskite Solar Cell (PSC) performance and correlate it to the occurrence of different phases.

The J-V curves of the devices were measured in a forward and reverse bias under the solar simulator (Fluxim, Litos Lite) with AM1.5 spectrum at a scan rate of 15 mV/s.

Vladimir Pejović, Epimitheas Georgitzikis, Itai Lieberman, Paweł E. Malinowski, Paul Heremans, David Cheyns

Adv Funct. Mat., (2022)

https://doi.org/10.1002/adfm.202201424

Image sensors based on colloidal quantum dots (CQDs) are expected to deliver affordable infrared image sensors to wider application scope. Here, a dual-band photodetector based on PbS CQDs is presented. By engineering the surface of CQDs, two oppositely facing pn junctions are fabricated in series, which enable sensing in two spectral channels. The presented photodetectors exhibit low dark current below 500 nA cm−2 at 1 V bias, a fast response measured in microseconds, as well as high external quantum efficiency, reaching 70% in NIR and 30% in SWIR.

Sudhir Kumar, Tommaso Marcato, Frank Krumeich, Yen-Ting Li, Yu-Cheng Chiu and Chih-Jen Shih

Nat Commun. (2022), 13, 2106

https://www.nature.com/articles/s41467-022-29812-5

The intrinsic light outcoupling efficiency of quantum dots remains considerably lower than the organic counterpart.

The authors, using the colloidal lead halide perovskite anisotropic nanocrystals (ANCs) as a model system, report a directed self-assembly approach to form an anisotropic nanocrystal superlattice of perovskite nanocrystals. The emission polarization in individual ANCs rescales the radiation from horizontal and vertical transition dipoles, effectively resulting in preferentially horizontal TDM orientation. The optimized single-junction QD LEDs showed peak external quantum efficiency of up to 24.96%, comparable to state-of-the-art organic LEDs.

Gregory Burwell, Oskar J. Sandberg, Wei Li, Paul Meredith, Matt Carnie, and Ardalan Armin

Sol. RRL 2200315, 1 , (2022)

DOI: 10.1002/solr.202200315

Compared to their use as organic solar cells (OSCs) for standard outdoor solar harvesting, indoor OPV (IOPV) devices operate at low light intensities and thus demonstrate different area-scaling behavior. In particular, it appears as though the performance of large-area IOPV devices is much less affected by the sheet resistances of the transparent conductive electrodes (a major limit in OSCs), but instead by factors such as their shunt resistance at low light intensities. Herein, the key parameters for improving the efficiency of large area IOPV using drift-diffusion and finite element modeling (FEM) are examined. The scaling behavior at low-light intensities is theoretically and experimentally probed and demonstrated using the model PM6:Y6 system.

Brinkmann, K.O., Becker, T., Zimmermann, F. et al.

Nature 604, 280–286 (2022).

doi.org/10.1038/s41586-022-04455-0

In this Nature paper the research team reached a new outstanding certified efficiency record of 23.1% with a two-terminal perovskite/organic solar cell.

Thanks to an ALD-deposited InOx interconnection layer, the current between the two subcells is perfectly matched at 14.1 mA/cm2. The high Voc of 2.15 V indicates an almost ideal interconnection between the two subcells.

These devices are using an organic absorber for the narrow-gap subcell, which doesn’t need the high-temperature processing of silicon and is more stable than the commonly used narrow-bandgap perovskites based on Sn.

With the software Setfos from FLUXiM AG, they carried out optical simulations to identify the wide bandgap perovskite that matches the organic subcell.

Stefano Sem, Sandra Jenatsch, Kleitos Stavrou, Andrew Danos,

Andrew P. Monkman and Beat Ruhstaller

J. Mater. Chem. C, 2022, Advance Article

doi.org/10.1039/D1TC05594A

Thermally-activated delayed fluorescence (TADF) compounds are promising materials used in emissive layers of organic light-emitting diodes (OLEDs). Their main benefit is that they allow the internal quantum efficiency of the OLED to reach up to 100% by converting non-radiative triplet states into radiative singlets. Besides the importance of having a high reverse intersystem-crossing rate, which governs triplet conversion, minimizing the non-radiative decay processes is also extremely important to reach high efficiency. In this study the researchers provide a new method to quantify not only the most important decay rates involved in the TADF process, but also the non-radiative decay rates of both singlet and triplet states individually from transient and steady state experimental optical data.

Setfos was used to perform electro-optical simulations.

Wei Meng, Kaicheng Zhang, Andres Osvet, Jiyun Zhang, Wolfgang Gruber, Karen Forberich, Bernd Meyer, Wolfgang Heiss, Tobias Unruh, Ning Li, Christoph J. Brabec

Joule, Volume 6, Issue 2, 2022,

https://doi.org/10.1016/j.joule.2022.01.011

This research provides new insights into the identification of strain at the buried interfaces of perovskite thin films and reveals the strain-associated physical mechanisms impacting the performance and stability of perovskite solar cells.

Setfos was used to simulate the IV curve of perovskite cells with/without strain. They included the graded interface in the simulation and also the increased trap density.

Stephen Amoah, Xiangyu Fu, Shichen Yin, Qi Dong, Chen Dong, and Franky So

CS Appl. Mater. Interfaces 2022, 14, 7, 9377–9385

https://doi.org/10.1021/acsami.1c21128

The light outcoupling efficiency of a top-emitting organic light-emitting diode (OLED) is only about 20%, and the majority of the light is trapped in the waveguide modes and surface plasmon polariton (SPP) modes. Extracting the trapped modes can reduce the device power consumption and improve the operating lifetime. In this study, the researchers demonstrate a top-emitting OLED structure with a dielectric spacer to suppress the SPP mode and with a patterned back mirror to extract the waveguide modes.

Setfos to simulate the power dispersion of the reference device and overlayed it with the experimental ARES data

Bingjun Wang, Sungho Nam, Saurav Limbu, Ji-Seon Kim, Moritz Riede, and Donal D. C. Bradley

Adv. Electron. Mater. 2022, 2101253

DOI: 10.1002/aelm.202101253

Copper(I) thiocyanate (CuSCN) is an effective interlayer material for hole injection and transport in organic electronic devices but its solution processing has conventionally utilized undesirable di-n-alkyl sulfide solvents such as diethyl- (DES) and dipropyl-sulfide (DPS). Herein, this paper reports on the use of N,N-dimethylformamide (DMF) and 1-methyl-2-pyrrolidinone (NMP) as alternative solvents for CuSCN interlayers and performs a detailed comparison of the resulting properties relative to films processed from DES and DPS and two other recent alternatives, dimethyl sulfoxide (DMSO) and ammonium hydroxide.

MIS-CELIV experiments were performed using the Fluxim PAIOS measurement platform with Characterization Suite 4.2 software.

Mingyun Kang, Syed Zahid Hassan, Seong-Min Ko, Changwon Choi, Juhee Kim, Santosh K. R. Parumala, Yun-Hi Kim, Yun Hee Jang, Jinhwan Yoon, Dong-Woo Jee, Dae Sung Chung

Advanced Materials

doi.org/10.1002/adma.202200526

When the intensity of the incident light increases, the photocurrents of organic photodiodes (OPDs) exhibit relatively early saturation, due to which OPDs cannot easily detect objects against strong backlights, such as sunlight. In this study, this problem is addressed by introducing a light-intensity-dependent transition of the operation mode, such that the operation mode of the OPD autonomously changes to overcome early photocurrent saturation as the incident light intensity passes the threshold intensity. The photoactive layer is doped with a strategically designed and synthesized molecular switch, 1,2-bis-(2-methyl-5-(4-cyanobiphenyl)-3-thienyl)tetrafluorobenzene (DAB). The proposed OPD exhibits a typical OPD performance with an external quantum efficiency (EQE) of <100% and a photomultiplication behavior with an EQE of >100% under low-intensity and high-intensity light illuminations, respectively, thereby resulting in an extension of the photoresponse linearity to a light intensity of 434 mW cm?2. This unique and reversible transition of the operation mode can be explained by the unbalanced quantum yield of photocyclization/photocycloreversion of the molecular switch. The details of the operation mechanism are discussed in conjunction with various photophysical analyses. Furthermore, they establish a prototype image sensor with an array of molecular-switch-embedded OPD pixels to demonstrate their extremely high sensitivity against strong light illumination.

To further verify the effect of DAB_c on gain generation, the researchers conducted a numerical simulation using the Fluxim’s Setfos software to fit the experimentally obtained OPD data and determine the relevant fitting parameters.

Takeshi Kamijo, Suzanne de Winter, Pradeep Panditha, and Eric Meulenkamp

ACS Applied Electronic Materials 2022 4 (2), 698-706

DOI: 10.1021/acsaelm.1c01116

The transparent conductive electrode (TCE) is a key component of organic light-emitting diodes (OLEDs). High resolution printed metal grids are a promising alternative to indium tin oxide (ITO). We present results for evaporated OLEDs with a printed copper (Cu) grid with line width below 3 μm. The use of a thick doped hole injection layer (HIL) prevented electrical shorts and resulted in good quality OLEDs with acceptable leakage current. We report a detailed analysis of the microscopic uniformity of light emission and compare the measured data with simulations based on finite element modeling (FEM) to investigate various factors that contribute to differences between the Cu grid OLED and ITO reference device. This insight resulted in design rules that enable a luminance of the Cu grid OLED that can potentially equal that of an ITO-based equivalent OLED by using a very fine pitch and narrow line width of 5 μm and 250 nm, respectively, within the capabilities of state-of-the-art printing technology.

The spatial luminance distribution was simulated by LAOSS - large area organic semiconductor simulation software.

Simon Zeder, Beat Ruhstaller, Urs Aeberhard

Phys. Rev. Applied 17, 014023 – Published 20 January 2022

https://doi.org/10.1103/PhysRevApplied.17.014023

Photon recycling (PR) is the re-absorption of internally emitted photons. Can it be another fundamental advantage of perovskites over other semiconductors in solar cells?

Simon Zeder and colleagues at FLUXiM AG discovered that PR could influence considerably the efficiency of MAPI-based solar cells. They coupled a wave optics approach with electronic transport simulations to treat photon recycling, rigorously. These simulations are showing that PR could increase the open-circuit voltage in pero-PVs by 50 mV in ideal conditions, and by 15 mV in the case of non-radiative recombination at the interfaces with MAPI. Further simulations show that the electron transporting layer (PCBM) and the back electrode (Ag) account for about 87% of the total parasitic absorption losses.

These results were obtained with the simulation software Setfos and can be used to design perovskite solar cells where photon recycling is an exploited beneficial effect.

Yue-Min Xie, Yong Cao et al.

Adv. Funct. Mater. 2022, 2112126.

https://doi.org/10.1002/adfm.202112126

Monolithic perovskite/organic tandem solar cells have attracted increasing attention due to their potential of being highly efficient while compatible with facile solution fabrication processes. This work has carefully optimized mixed halide wide-bandgap perovskite (MWP) films by introducing a small amount of formamidinium (FA+) cations into the basic composition of MA1.06PbI2Br(SCN)0.12, which provides an effective means to modulate the crystallization properties and phase stability of the films. At optimized conditions, the MA0.96FA0.1PbI2Br(SCN)0.12 forms high-quality films with grain boundaries homogeneously passivated by PbI2, leading to a reduction in defect states and an enhancement in phase stability, enabling the fabrication of perovskite solar cells with a power conversion efficiency(PCE) of 17.4%. By further integrating the MWP front cell with an organic BHJ (PM6:CH1007) rare cell composed of a non-fullerene acceptor with absorption extended to 950 nm, a tandem cell with PCE over 21% is achieved.

PAIOS was used to analyze these solar cells with Electrochemical Impedance Spectroscopy

Le Wang, Feng Yu, Hong Zhao, Yufei Wang, Tianfu Gu, Wenyan Su, Quanbin Liang, Zhenfang Tang, Hongbin Wu, Lintao Hou

Organic Electronics, Volume 101, 2022

https://doi.org/10.1016/j.orgel.2021.106423

In this paper the researchers compare the performance of fullerene and non-fullerene based solar cells fabricated with spin, blade or spray coating. They find that spin-coated device have higher performance and analyse it with drift-diffusion simulations of IV curves.

Paios was used to calculate Voc vs. L to substantiate more SRH recombination in spray coated device. They also used TPV and TPC to further substantiate their findings related to different aggregation.

Kevin Sutanto, Nurul Ridho Al Amin, Chih-Hsin Chen, Dian Luo, Chien-Hsin Chen, Sajal Biring, Chih-Chien Lee, Shun-Wei Liu

Organic Electronics, Volume 103, 2022, 106454, ISSN 1566-1199,

https://doi.org/10.1016/j.orgel.2022.106454.

Here the researchers report on a WO3/Al/Al:Ag anode which is demonstrated in a red OLED with superior performance compared to the ITO reference device. Better performance is due to narrower emission spectrum, improved outcoupling, lower turn-on voltage/better charge injection.

Setfos was used to simulate the forward emission spectrum and performed mode analysis for different ETL thicknesses.

Paios was also used to perform Impedance Spectroscopy at different voltages to check injection/accumulation of charges, performed C-V to analyse onset and show Transient Electroluminescence.

Perini, Carlo and Rojas-Gatjens, Esteban and Ravello, Magdalena and Castro Mendez, Andres Felipe and Hidalgo, Juanita and An, Yu and Li, Ruipeng and Silva-Acuña, Carlos and Correa-Baena, Juan-Pablo

doi.org/10.2139/ssrn.3921344

10 Sep 2021

The impact on device stability of the bulky cation-modified interfaces in halide perovskite solar cells is not well-understood. In this paper the research team demonstrate the thermal instability of the bulky cation interface layers used in some of the highest performing solar cells to date.

The photovoltaic performance was evaluated using a Fluxim Litos Lite setup, equipped with a Wavelabs Sinus-70 AAA solar simulator with AM1.5 spectrum for excitation. The current voltage (J-V) characteristics were acquired with forward and reverse scans at a scan rate of 50 mV s-1. The stabilized power output was acquired using a maximum power point tracking algorithm for 60 s. Devices were not preconditioned before measurement. Masking was used during the measurement, defining a pixel area of 0.0625 cm2. Nitrogen was flown in the measurement chamber during characterization. No temperature control was applied. Aging tests were performed using a Fluxim Litos setup, using 1 Sun equivalent illumination with no UV-component, holding the substrates at 55 °C in a N2 atmosphere and using a maximum power point tracking algorithm. Every 12 h a J-V scan in reverse and forward direction was automatically acquired.

Ma, D., Lin, K., Dong, Y. et al.

Nature 599, 594–598 (2021).

doi.org/10.1038/s41586-021-03997-z

Light-emitting diodes (LEDs) based on perovskite quantum dots have shown external quantum efficiencies (EQEs) of over 23% and narrowband emission, but suffer from limited operating stability.

In this paper the researchers fabricate a more stable PeroLED by using fluorinated triphenylphosphine oxides to control the thickness distribution and passivate the surface of perovskite quantum wells (QWs) deposited in a film. The additive forms hydrogen bonds with the cations and gives energetically monodispersed QWs on a uniform film with high photoluminescence quantum yield. The fabricated pero-LEDs show green narrow emission with an EQE of 25.6% and an operating half-life of two hours at an initial luminance of 7,200 cd/m2.

The EQE is close to the theoretical outcoupling efficiency of these LEDs, as predicted by the simulation software Setfos. The optical simulations were performed using the Chance–Prock–Silbey model in Setfos.

Xu, Qiwei; Cheong, I Teng; Meng, Lingju; Veinot, Jonathan G. C.; Wang, Xihua

ACS Nano 2021, 15, 11, 18429–18436.

doi.org/10.1021/acsnano.1c08002

In this paper the researchers test different Si passivation tricks to optimize PbS quantum dot detectors. The two-step passivation device shows an EQE of 31% at 1280 nm and -4V.

Paios was used to perform TPV and TPC measurements to confirm longer lifetime and faster extraction, respectively, using the two-step process. This is explained by trap passivation.

Tianqi Niu, Yue-Min Xie, Qifan Xue, Sangni Xun, Qin Yao, Fuchao Zhen, Wenbo Yan, Hong Li, Jean-Luc Brédas, Hin-Lap Yip, Yong Cao

Adv. Energy Mater. 2021, 2102973.

doi.org/10.1002/aenm.202102973

Here researchers developed a stable and efficient Perovskite solar cell by combining the efficiency of 3D perovskites and the high stability of 2D perovskites.

They compared PSCs with 2D perovskites based on diammonium ligands with different concentrations and sizes. The 2,2-(ethylenedioxy)bis(ethylammonium) (EDBE) cations guarantee a homogenous growth and good coverage of the 2D perovskite layer on top of the 3D absorber. The 2D layer improves photo-, thermal- and humidity stability while increasing the efficiency by 2.5% compared to the control device. The power conversion efficiency (PCE) of the best solar cell was 22.6%.

The boost in performance is the result of decreased charge recombination and improved charge extraction as confirmed by TPC and TPV measurements carried with Paios.

Yi-Sheng Chen, Dian Luo, Wei-Chih Wei, Bo-Lin Chen, Tzu-Hung Yeh, Shun-Wei Liu, and Ken-Tsung Wong

Adv. Optical Mater. 2021, 2101952

DOI: 10.1002/adom.202101952

Prof. Wong and colleagues at the National Taiwan University tailored a special blend of organic molecules to reach a remarkable efficiency. This work is a perfect example of how to fine-tune the OLED emission via a combined simulation/experiment approach.

The team developed spirobifluorene-cored (SF) donors and blended them with CN-T2T acceptor for exciplex formation. This combination gives an electroluminescence peak at 584 nm. The emission increases to 760 nm with the further inclusion of the fluorescent emitter TTDSF. An optimized microcavity effect brings the emission to 774 nm.

The simulation software Setfos from allowed them to find the optimal thickness of the acceptor material (or ETL), and to optimize the optical cavity. The researchers measured an impressive EQE of 5.3% and stable performance of almost 300 hours for the optimized device.

Haibing Xie, Zaiwei Wang, Zehua Chen, ..., Michael Gratzel,

Anders Hagfeldt, Monica Lira-Cantu et al.

Joule Volume 5, Issue 5, 19 May 2021, Pages 1246-1266

doi.org/10.1016/j.joule.2021.04.003

"Add H3pp to perovskite to improve performance while maintaining high efficiency (21% maintained after 1000 h @ MPP).

Perform various characterization and simulation techniques to demonstrate that the addition of H3pp leads to a passivation of the shallow defects, which are not affecting the performance but the device stability."

Voc vs L was performed using Paios to demonstrate negligible difference in n_id -> no difference in SRH.

C-f was carried out to demonstrate an effective reduction in ion migration and charge accumulation in the better device.

TPC and OCVD confirm negligible changes in the charge transport mechanism.

Xie, Lisha; Xie, Junni; Wang, Shurong; Chen, Bin; Yang, Chenguang; Wang, Zhen; et al.

ACS Appl. Mater. Interfaces 2021, 13, 22, 26093–26101

doi.org/10.1021/acsami.1c06216

In this paper the researchers report on a oligomer treatment of MAPI films which efficiently passivate defects by coordination with Pb ions. With additional improvements in crystallization and charge transport properties, the resulting cell had a PCE of 21.23% and showed better stability.

Paios was used to determine shorter TPC decay time and longer TPV lifetime was used to confirm the improved charge extraction properties.

Pang Wang, Wei Li, Oskar J. Sandberg, Chuanhang Guo, Rui Sun, Hui Wang, Donghui Li, Huijun Zhang, Shili Cheng, Dan Liu, Jie Min, Ardalan Armin, and Tao Wang

Nano Lett. 2021, 21, 18, 7845–7854

Publication Date:September 10, 2021

https://doi.org/10.1021/acs.nanolett.1c02897

In this paper the researchers utilize the wide-bandgap CsPbI2Br semiconductor and narrow-bandgap PM6:Y6-BO blend to fabricate perovskite/organic tandem solar cells with an efficiency of 21.1% and a very small tandem open-circuit voltage loss of 0.06 V.

The photon absorption rate distribution of polyTPD and PBDB-T-Si based TSCs were simulated using the transfer-matrix model via SETFOS (version number: SETFOS 5.1)

Kai Oliver Brinkmann, Tim Becker, Florian Zimmermann, Cedric Kreusel, Tobias Gahlmann, Tobias Haeger, Thomas Riedl

Solar RRL (IF8.582), Pub Date : 2021-07-17,

doi/10.1002/solr.202100371

Optical simulations have been performed with the simulation software SETFOS that is based on a transfer matrix algorithm to calculate optical absorption, reflection, and transmission of a given assembly of layers. With the emergence of highly efficient perovskite solar cells in both single- and multijunction architectures, there is an abundance of reports of extremely high external quantum efficiencies (EQE) up to 98%.

These reports appear somewhat unrealistic and are sometimes subject to doubts or concerns of erroneous EQE measurements. In this report the researchers discuss and explain the root cause of the high EQE by a combination of experimental data and optical simulations.

Chin-Yiu Chan, Masaki Tanaka, Yi-Ting Lee, Yiu-Wing Wong, Hajime Nakanotani, Takuji Hatakeyama, and Chihaya Adachi

Nature Photonics, 15, 203–207, (2021)

https://www.nature.com/articles/s41566-020-00745-z

It is challenging to produce stable blue OLEDs with high efficiency and color purity. The researchers fabricated a new OLED showing pure-blue emission with high efficiency and stability. Their optimized device consists of a 2-unit stacked tandem OLED with a hyperfluorescent emitting layer. Setfos was used to fit angular photoluminescence data and determine the orientation of the dipoles of the TADF emitter.

Vasilopoulou, M., Mohd Yusoff, A.R.b., Daboczi, M. et al.

Nat Commun 12, 4868 (2021).

doi.org/10.1038/s41467-021-25135-z

In this paper, the team designed blue OLEDs with a new Hole Transport Material (HTM). By engineering the formation of exciplex excitons at the EML/ETL interface and subsequent FRET they managed to fabricate OLEDs with high efficiencies and turn-on voltage below band-gap. The device lifetime is longer than previously reported blue OLEDs, even if degradation due to the instability of the excited host molecule (typical in TADF OLEDs) is still an issue.

Setfos was used to help extract the dipole orientation of the TADF emitter from the analysis of angle-dependent PL spectra.

Ennio Luigi Comi,Evelyne Knapp, Stefano Weidmann, Christoph Kirsch, Sandra Jenatsch, Roman Hiestand, Beat Ruhstaller

Solar Energy Advances

Volume 1, 2021, 100003

doi.org/10.1016/j.seja.2021.100003

In this paper the researchers present a FEM (Finite Element Method) software that supports the upscaling process from small to large area solar cells and tackles the efficiency loss factors of scaling solar cells such as shunts and increasing series resistance caused by the sheet resistance of the electrodes.

Read the full open access paper here

Lin Z, Guan W, Cai W, et al.

Energy Sci Eng. 2021;9:502–508.

doi/epdf/10.1002/ese3.870

Lamination technique is one of the most promising and effective approaches to produce flexible organic solar cells (OSCs). In this study, flexible ITO-free OSCs were successfully fabricated by lamination technique under the optimized temperature and pressure. This work illustrates that anode interface engineering has a significant effect on the improvement of performance of roll-to-roll laminated and self-encapsulated OSCs.

The light intensity dependence and spectroscopy (IS) as well as photo-induced charge extraction by linearly increasing volt-age (photo-CELIV) measurements were performed using an all-in-one electrical and optical characterization platform of Paios.

Zijian Deng, Xichuan Yang, Kaiyuan Yang, Li Zhang, Haoxin Wang, Xiuna Wang, and Licheng Sun

ACS Sustainable Chemistry & Engineering 2021 9 (15), 5252-5259

DOI: 10.1021/acssuschemeng.0c08195

Redox mediators play a major role in determining the photocurrent and photovoltage in dye-sensitized solar cells (DSSCs). In this study, two helical copper(I) complexes are synthesized and applied to TBP-free solar cells.

As part of this study the researchers used Paios to perform Intensity-modulated photovoltage spectroscopy (IMVS)

Mengmeng Chen, Muhammad Akmal Kamarudin, Ajay K. Baranwal, Gaurav Kapil, Teresa S. Ripolles, Kohei Nishimura, Daisuke Hirotani, Shahrir Razey Sahamir, Zheng Zhang, Chao Ding, Yoshitaka Sanehira, Juan Bisquert, Qing Shen, and Shuzi Hayase

ACS Applied Energy Materials 2021 4 (6), 5615-5624

DOI: 10.1021/acsaem.1c00413

In this paper the researchers explore the fabrication of the wide band gap (1.61 eV) ASnI2Br perovskite solar cells through the optimization of formamidinium and guanidinium content to improve the efficiency from 1.68 to 7.00%. This work provides proof that tin-halide perovskite solar cells have the potential in the fabrication of lead-free all-perovskite tandem solar cells.

The researchers used Paios to perform, under light, intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS).

Felix Lang, Eike Köhnen, Jonathan Warby, Ke Xu, Max Grischek, Philipp Wagner, Dieter Neher, Lars Korte, Steve Albrecht, and Martin Stolterfoht

ACS Energy Letters 0, 6

DOI: 10.1021/acsenergylett.1c01783

In this paper the researchers present a thorough subcell diagnosis methodology to reveal deep insights into the practical efficiency limitations of state-of-the-art perovskite/silicon tandem PVs.

Setfos was used by the researchers to simulate band diagrams with either aligned energy levels or energy offsets in the perovskite subcell.

Yuying Cui, Shurong Wang, Chengbo Li, Aili Wang, Jing Ren, Chenguang Yang, Bin Chen, Zhen Wang and Feng Hao

Green Chem., 2021,23, 3633-3641

DOI: 10.1039/d1gc00599e

A green co-antisolvent of propyl acetate is induced to adjust the degree of supersaturation in diethyl ether, enabling pinhole-free, smooth, and uniform perovskite thin films. A high power conversion efficiency up to 20.61% was achieved in a p–i–n inverted MAPbI3 PSC with an impressive fill factor (FF) over 84%.

Jarla Thiesbrummel, Vincent M. Le Corre, Francisco Peña-Camargo, Lorena Perdigón-Toro, Felix Lang, Fengjiu Yang, Max Grischek, Emilio Gutierrez-Partida, Jonathan Warby, Michael D. Farrar, Suhas Mahesh, Pietro Caprioglio, Steve Albrecht, Dieter Neher, Henry J. Snaith, Martin Stolterfoht

Adv. Energy Mater. Sept. 2021, 2101447

doi.org/10.1002/aenm.202101447

In the paper, the researchers performed an analysis of current (performance) losses in PPV devices.

1) analyse changes in PLQY upon time (Voc -> Jsc) and link it to extraction problems caused by ions

2) perform various transient electric measurements to analyse electronic and ionic charge densities

They used the Absorption and Drift-Diffusion modules of Setfos to simulate transient current decay with mobile ions and 1) extract the ion density by fitting with experimental data, 2) show that electronic doping would not cause a current decay in contrast to ions and their experiments.

Qiyu Chen, Jincheng Luo, Rui He, Huagui Lai, Shengqiang Ren, Yiting Jiang, Zhenxi Wan, Wenwu Wang, Xia Hao, Ye Wang, Jingquan Zhang, Iordania Constantinou, Changlei Wang, Lili Wu, Fan Fu, Dewei Zhao

Adv. Energy Mater. 2021, 2101045.

doi.org/10.1002/aenm.202101045

In the paper, the researchers analyze the effect of SnF2 additives on the performance of lead-tin perovskite solar cells. The Paios dark IV measurement was used to detect saturation current and attribute this to the defect density.

Hyeong Woo Bae, Yong Woo Kwon, Myungchan An, Junmo Kim, Jang Hyuk Kwon, and Donggu Lee

ACS Appl. Electron. Mater. 2021, 3, 7, 3240–3246

doi.org/10.1021/acsaelm.1c00406

In this paper, the researchers fabricated a tandem white OLED with a 20nm thin charge generation unit (CGU). Test subunits as well as first and second maxima (of the radiance plot) experimentally. Setfos was used to optimize layer thicknesses to get radiance peaks.

T. Ichikawa, A. Takagi, N. Yamada, K. Itonaga, H. Nakanotani, C. Adachi

Proceedings Volume 11788, Digital Optical Technologies; 117880P (2021)

doi.org/10.1117/12.2595135

In this paper, the researchers develop material and NIR-OLED stack which is finally integrated into a microdisplay. The application would be sensing. Setfos was used to optimize the cavity (tuning of HAT-CN layer).

Junmo Kim, Jeong Ha Hwang, Yong Woo Kwon, Hyeong Woo Bae, Myungchan An, Wonho Lee, Donggu Lee,

Organic Electronics, Volume 97, 2021, 106261,

doi.org/10.1016/j.orgel.2021.106261.

This report details the use of SiNx as encapsulation material. Thickness variation results on EQE were supported by I_OC simulations performed by Setfos.

Hyunsu Cho, Jinouk Song, Jin-Wook Shin, Jaehyun Moon, Byoung-Hwa Kwon, Jeong-Ik Lee, Seunghyup Yoo, and Nam Sung Cho

Optics Express (IF3.894), Pub Date : 2021-07-07

DOI: 10.1364/oe.430149

Description

In this paper, the researchers fabricated graphene-based electrodes for OLEDs. Multi-layer graphene electrodes were doped with TCNQ and their optical constants are measured.

Setfos was used to perform an angle-dependent emission simulation of the OLED with graphene electrodes to demonstrate the necessity and suitability of the nk data.

Dong Li, Jingwen Feng, Youqin Zhu, Zhigao Lu, Chen Pei, Zhuo Chen, Yanzhao Li, Xinguo Li & Xiaoguang X

Nano Res. (2021).

doi.org/10.1007/s12274-021-3596-4

In this paper, the researchers fabricated QLEDs with a top and bottom emission structure. They first electrically optimized the device (charge balance) and then optically improved the device in order to then change to a different ETL which optimizes both charge balance and optics at the same time. Setfos was used to perform an optical simulation of the QLEDs with different ETL thicknesses.

Danyu Cui, Xiao Liu, Tianhao Wu, Xuesong Lin, Xinhui Luo, Yongzhen Wu, Hiroshi Segawa, Xudong Yang, Yiqiang Zhang, Yanbo Wang, Liyuan Han

Adv. Fun. Mat. Volume31, Issue25, June 16, 2021, 2100931

doi.org/10.1002/adfm.202100931

Description:

In this paper, the researchers fabricated tin-based perovskite solar cells with improved performance thanks to a cooled (0°) precursor solution. The latter leads to larger grain sizes which enhance the charge carrier lifetime (-> enhanced Voc) and reduces the oxygen penetration (-> longer lifetime) and subsequent reaction in the film. Paios was used to perform TPV and TPC experiments in order to demonstrate the longer charge carrier lifetime and the enhanced charge extraction properties of the 0° -device, respectively.

Zhiwei Peng, Yuhan Gao, Guohua Xie

Molecules 2021, 26(6), 1670

doi.org/10.3390/molecules26061670

Description:

In this paper, the researchers investigated the effect of different dopants for the HTL (PTAA) in perovskite QD LEDs. Doping generally improved the peak efficiency compared to the undoped PTAA device. Paios was used to perform TEL and impedance spectroscopy to support the improved charge transport behavior upon electrical doping.

M. Lekshmi, S. Saroon, Ancy Albert, C.O. Sreekala

Materials Today Proceedings, Volume 46, Part 8, 2021, Pages 3114-3120

doi.org/10.1016/j.matpr.2021.02.682

Description:

In this work, a comparative study of inverted perovskite solar cells with different hole-transporting materials were fabricated out by simulation using the simulation software Setfos

Zhenxi Wan, Shengqiang Ren, Huagui Lai, Yiting Jiang, Xiaojun Wu, Jincheng Luo, Yunfan Wang, Rui He, Qiyu Chen, Xia Hao, Ye Wang, Lili Wu, Iordania Constantinou, Wen-Hua Zhang, Jingquan Zhang, Dewei Zhao

Adv. Mat. Int. Volume8, Issue9 May 7, 2021, 2100135

doi.org/10.1002/admi.202100135

Description:

In this paper, the researchers used a vacuum treatment to improve the performance (Voc and Jsc) of FA0.75MA0.25SnI3 perovskite solar cells.

Paios was used to perform dark IV measurements to support interface trap reduction via decreased J0.

J. I. Khan, S. Alsaggaf, R. S. Ashraf, B. Purushothaman, N. Chaturvedi, I. McCulloch, F. Laquai

Phys. Stat. Sol. (RRL) (2021)

https://doi.org/10.1002/pssr.202100206

The authors investigate charge carrier generation and recombination dynamics in blends of a novel wide-bandgap germanium-containing donor polymer, namely PEHGeNDT-BT, paired with either O-IDTBR or O-IDTBCN as a non-fullerene acceptor in BHJ solar cells by (ultrafast) transient spectroscopy and time-delayed collection field (TDCF) experiments. Carrier drift-diffusion simulations of the devices’ current-voltage (J-V) characteristics confirm that the experimentally determined kinetic parameters and process yields can reproduce the measured J-V curves under steady-state solar illumination.

Z. Chen, J. Wang, H. Jin, J. Yang, Q. Bao, Z. Ma, W. Tress and Z. Tang

J. Mater. Chem. C (2021)

https://pubs.rsc.org/en/content/articlelanding/2021/tc/d1tc00745a

The authors studied the impact of the resistance of a sol-gel-grown ZnO interlayer on the efficiency of an organic solar cell. They find that the UV-induced doping effect leads to a significantly reduced ZnO resistance, which gives rise to an underestimated photoactive area and thus overestimated short-circuit current density (Jsc) Therefore, the validity of the argument that high-resistance interlayers do not lead to overestimated Jsc should always be carefully evaluated. Current-voltage characteristics were simulated using the large-area semiconductor simulator LAOSS

E Knapp, M Battaglia, T Stadelmann, S Jenatsch, B Ruhstaller

8th Swiss Conference on Data Science, Lucerne, Switzerland, 9 June 2021

https://160.85.104.64/handle/11475/22414

In this paper, the authors combine the use of machine learning and a semiconductor device modelling tool (Setfos) to extract the material parameters from measurements and inturn train their machine learning model with synthetic training data originating from a semiconductor simulator. In a second step, the machine learning model is applied to a measured data set and determines the underlying material parameters. This novel and reliable method for the determination of material parameters paves the way to further device performance optimization.

Urs Aeberhard, Simon Zeder, Beat Ruhstaller

Optics Express, 29, (2021), 14773

PDF

Dr. Aeberhard and colleagues at FLUXiM AG presented a theoretical description of light emission, propagation, and re-absorption in semiconductor multilayer stacks is derived based on the transverse Green’s function of the electromagnetic field in the presence of a complex dielectric. The framework obtained is shown to reproduce the generalized Kirchhoff relations between the luminescent emission from metal halide perovskite slabs under uniform excitation and the slab absorptance of light with arbitrary angle of incidence.

G. Burwell, N. Burridge, E. Bond, W. Li, P. Meredith, and A. Armin

Adv. Electron. Mater. (2021), 2100192,

https://onlinelibrary.wiley.com/doi/10.1002/aelm.202100192

Finite element modeling is used to investigate the relevant design parameters and to estimate figures of merit for realistic large-area OPVs. It is shown that the scalability of devices with metallic grids improves significantly when grids are implemented at micrometer scales. Representative silver grids are fabricated and the optical and electrical properties of the resulting structures are measured. These findings indicate that metallic grids can be designed to develop large-area solution-processed solar cells with currently available fabrication techniques.

Benjamin T. Feleki, Christ H. L. Weijtens, Martijn M. Wienk, and René A. J. Janssen

ACS Appl. Energy Mater. 2021, 4, 3033−3043

https://pubs.acs.org/doi/pdf/10.1021/acsaem.0c02653

The authors discovered that in a perovskite solar cell with an opaque substrate, parasitic optical absorption can be minimized by using a thin organic Hole Transport Layer, called NPB. The optical simulations of these solar cells were performed by using the transfer matrix method in Setfos. By exploiting simulations, designed an optimal stack before performing the actual experiments.

Yungui Li, Naresh B. Kotadiya, Bas van der Zee, Paul W. M. Blom, and Gert-Jan A. H. Wetzelaer

Adv. Optical Mater. 2021, 2001812,

https://onlinelibrary.wiley.com/doi/full/10.1002/adom.202001812

The authors developed a numerical model to simulate the fraction of photons coupled to air for OLEDs with a broad recombination zone. The dipole orientation of the CzDBA neat film was determined with Phelos by fitting the angular dependence of photoluminescence with Setfos software from Fluxim.

T. Dai, X. Li, Y. Zhang, X. Zhou, Y. Zhu, J. Zhou, D. Xu T. Lin

Solar RRL (5 March 2021);

doi: 10.1002/solr.202100151.

In this paper, the researchers analyze the effect of the PFN-Br interface layer on the performance and degradation of an OPV. The degradation (electric load) was showing a reduced FF and Jsc which they attributed to the contact modification, as it was absent for the devices without PFN-Br. The researchers used the characterization tool Paios. They performed multiple measurements to support the charge collection/extraction problem due to PFN-Br interface during degradation.

Tom P. A. van der Pol, René A. J. Janssen et al.

J. Phys. Chem. C March 4, 2021

https://doi.org/10.1021/acs.jpcc.0c11377

In this paper, the researchers analyze the performance of nonfullerene acceptors blends fabricated with solvent mixtures. The researchers used the Emission module of the simulation software Setfos to correct for self-absorption and interference effects of the PL and EL signals.

Jörn Langenickel; Alexander Weiß; Jörg Martin; Thomas Otto; Harald Kuhn

SPIE 11706, Light-Emitting Devices, Materials, and Applications XXV, 117061R (5 March 2021);

doi: 10.1117/12.2578153

In this paper, the researchers analyze the influence of organic HTL on the QLED dynamics and mobilities in HTL and correlate this with the dynamics of the QLED (-> determined by Modulated Electroluminescence Spectroscopy (MELS)). The researchers used the characterization tool Paios. In particular, the phase shift from MELS was used as a figure of merit for the QLED dynamics.

Rui He, Dewei Zhao et al.

nanoph-2020-0634 2021,

DOI: 10.1515/nanoph-2020-0634

In this paper, the researchers work on wide bandgap perovskite and achieve an efficiency of 17.12% for their inverted TBB-doped PSC with an enhanced Voc of 1.19 V. The improvement is due to (1) better alignment of the conduction band with C60 and (2) larger grain sizes leading to reduced bulk recombination." The researchers used the characterization tool Paios. TPV (TPC) shows increased (decreased) lifetime (charge extraction time) for 0.3% TBB-doped perovskite solar cell confirming the TrPL lifetimes (UPS energy alignment) data also in the device. IS fitting was interpreted as higher recombination resistance.

S. K. Kim, Dr. M. J. Park, Prof. J. H. Kwon

Adv. Photonics Res. 2021, 2000122

DOI: 10.1002/adpr.202000122

In this paper, the researchers optimize TEOLEDs with blue emitter, with a special focus on the top electrode. The researchers used the emission module of the simulation software Setfos to simulate different stacks and compare the results with the experiments.

Fuzong Xu, Stefaan De Wolf, et al.

Small Sci. 2021, 2000044

DOI: 10.1002/smsc.202000044

In this paper, the researchers fabricated MAPI perovskites using slot-die coating with KSCN additive, and a modified solvent mixture. These modifications lead to higher performance (avg PCE 20.14%, all key figures improved), lower hysteresis, and a longer device lifetime. The researchers used the characterization tool Paios to increase TPV lifetime, larger recombination resistance from IS and shorter TPC decay times for KSCN modified cells to support better charge transport properties and lower defect densities.

Jaeho Lee, Jinouk Song, Jaehyeok Park, Seunghyup Yoo

Adv. Opt. Mat. 2021, 202002182

DOI: 10.1002/adom.202002182

In this paper, the researchers analyze the effect of low refractive index materials on outcoupling efficiency and different loss channels. The researchers used the emission module of the simulation software Setfos to produce benchmark optical simulations.

Chan, CY., Tanaka, M., Lee, YT. et al.

Nat. Photonics (2021).

https://doi.org/10.1038/s41566-020-00745-z

Organic light-emitting diodes (OLEDs) are a promising light-source technology for future generations of display. Despite great progress it is still challenging to produce blue OLEDs with sufficient colour purity, lifetime and efficiency for applications. This study presents a “3-component blue EML (new TADF assistant dopant; v-DABNA as (TADF)-narrow emitter; mCBP host) with pure color thanks to DABNA, but also higher EQE and LT95 thanks to the new emitter and the 3-component system. Use of the blue EML in a tandem configuration yielded an even higher EQE of 41%, lower CIEy coordinate (more blue) and better LT95 of >300 h (everything at 100 cd/m^2)." The Setfos Emission module was used for the emitter orientation fit. DABNA is more orientated than new emitter, yielding a higher EQE in the ternary EML.

Y. Liu, J. Wang, et al.

ACS Applied Nano Materials Article ASAP

DOI: 10.1021/acsanm.0c02797

A computer simulation study and parameter analysis are performed to demonstrate the fluorescent properties of the organic light-emitting diode (OLED) device structure. Setfos emission module was used in this simulation study.

Sharma, A., Das, T.D.

Opt Quant Electron 53, 83 (2021)

https://doi.org/10.1007/s11082-020-02707-9

In this paper, the researchers performed simulations and parameter analyses to demonstrate the fluorescent properties of the OLED device structure. Setfos emission module was used in this simulation study.

Hye In Yang, Jang Hyuk Kwon, et al.

Organic Electronics, Volume 89, 2021, 106031, ISSN 1566-1199,

https://doi.org/10.1016/j.orgel.2020.106031

This paper presents an efficient and stable green inverted organic light-emitting diode (IOLED) using multifunctional and strong nucleophilic quality electron transport material. Ag is used as n-type doping for ETMs (comparison to more popular Li). Ag doping results in similar performance but the stability is improved. The Setfos emission module was used to optimize the layer stack.

Dyson, M. J., van der, T. P. A., Meskers, S. C. J.

Adv. Optical Mater. 2021, 2001997.

https://doi.org/10.1002/adom.202001997

This study analyses the effect of cavity and self-absorption ("extrinsic") effects on measured PL spectra, focussing on 0-0/0-1 ratios. Setfos was used by the researchers to simulate absorption and emission of thin films.

Diogo Castro, Vera C. M. Duarte, and Luísa Andrade

ACS Omega Article ASAP

DOI: 10.1021/acsomega.2c03560

The increasing demand for solar energy has led researchers worldwide to develop new photovoltaic technologies.

Among these, perovskite materials are one of the most promising candidates, with a performance evolution unparalleled in the photovoltaic field.

However, this thin-film technology is not yet available at a commercial level, mainly due to upscaling issues. This work studied the best design options for upscaling single cells into modules by minimizing electrical losses in the device substrates.

Fluxim`s Laoss software for upscaling was used to test and optimize different substrate sizes and designs and to predict several performance outcomes from experimentally fabricated single cells.

The results showed that it is possible to retain most of the energy production when upscaling from a single cell to a module if the appropriate design for an efficient monolithic device is used.

Bingjun Wang, Hao Ye, Moritz Riede, and Donal D. C. Bradley

ACS Applied Materials & Interfaces Article ASAP (Jan, 2021)

DOI: 10.1021/acsami.0c18490

The aim of this research is to fabricate Perovskite LEDs with beta-phase-induced ordered EML. The 5% ordered film shows improved efficiency and lifetime compared to the 0% beta-phase Perovskite LED. Paios was used to balance electron-hole mobilities for beta-phase samples, measured by MIS-CELIV and differential susceptance, which is argued to lead to a better charge balance factor and thus a higher EQE.