Open-circuit and short-circuit loss management in wide-gap perovskite p-i-n solar cells

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.