Impedance analysis of perovskite solar cells: a case study

Abstract

Metal halide perovskites are mixed electronic–ionic semiconductors with an extraordinarily rich optoelectronic behavior and the capability to function very efficiently as active layers in solar cells, with a record efficiency surpassing 23% nowadays. In this work, we carry out an impedance spectroscopy analysis of two perovskite solar cells with quite distinct optical and electrical characteristics, i.e. MAPbI₃ and CsPbBr₃-based devices. The main aim of the analysis is to establish how, regardless of the inherent complexity of the impedance spectrum due to ionic effects, information like ideality factors, recombination losses and the collection efficiency can be qualitatively and quantitatively assessed from impedance experiments under operating conditions.