Ultrafast Photo-induced Carrier Dynamics of FAPbI3-MAPbBr3 Perovskite Films Fabricated with Additives and a Hole Transport Material

Abstract In this study, mixed perovskite films of formamidinium lead triiodide (HC(NH2)2PbI3, FAPbI3) and methylammonium lead tribromide (CH3NH3PbBr3, MAPbBr3) were fabricated differently with solution additive methods and a presence of a hole transport material (HTM). We utilized ultrafast time-resolved transient absorption spectroscopy (TAS) in order to investigate the carrier generation and decay dynamics. The photo-induced carrier dynamics changes according to each additive methods and applying a HTM. The HTM affects dominantly a TA decay constant of long-time scale. On the other hand, additive methods reduce a time constant of short-time scale and also increase the density of the photo-induced carrier.