An embedded interfacial network stabilizes inorganic CsPbI3 perovskite thin films

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.