• Urbaniak, A.; Czudek, A.; Dagar, J.; Unger, E.L.: Capacitance spectroscopy of thin-film formamidinium lead iodide based perovskite solar cells. Solar Energy Materials and Solar Cells 238 (2022), p. 111618/1-7

10.1016/j.solmat.2022.111618
Open Access Version

Abstract:
This work concerns the interpretation of capacitance spectroscopy results in perovskite-based solar cells. Based on the deep level transient spectroscopy and admittance spectroscopy results, we present arguments that the observable signals in perovskite-based solar cells come from anion migration rather than being a response from deep trap energy levels. The ion migration parameters, such as activation energy and ion concentration, are calculated and compared to theoretical values for different migration paths of ions in perovskites. Those parameters evolve with time, reflecting in the degradation of the cells, which we propose to link with a change in the anion migration path in perovskite.