Charge traps in lead-halide perovskites with different grain sizes

It is crucially required to understand charge traps in CH₃NH₃PbI₃ perovskites, which severely affect the charge recombination mechanism and hence have a critical impact on photovoltaic performance. Herein, we studied the photoexcited dynamics of CH₃NH₃PbI₃ perovskites with different grain sizes by measuring the intensity dependence of time-resolved photoluminescence (PL). As a result, we found that the PL decay for all the samples can be well analyzed using bimolecular radiative recombination and trap-assisted Shockely–Read–Hall recombination models. We discuss how the PL dynamics impact the photovoltaic performance of CH₃NH₃PbI₃ perovskite solar cells on the basis of the recombinatio