界面种子层修饰策略制备高性能CsPbIBr2光电探测器

Abstract

Objective Photodetectors can convert incident light into electric signals and are widely used in many fields such as image sensing, optical communication, environmental monitoring, and biological detection. In recent years, allinorganic metal halide perovskite CsPbIBr 2 has been concerned in photoelectric detection due to its high light absorption coefficient, high charge carrier mobility, and low defect density. On the one hand, CsPbIBr 2 film is susceptible to ambient humidity, so it is not usually prepared under an atmospheric environment but in glove boxes by methods such as spin coating. On the other hand, on account of uncontrolled nucleation during crystallization, CsPbIBr 2 film has poor morphology and crystallinity, which results in weak photoelectric characteristics and instability of its photodetector. In order to overcome these problems, the morphology, crystallinity, and water/oxygen resistance of CsPbIBr 2 thick film can be improved by additives and interface layer strategies. In this study, we employ an interfacial seed layer modification strategy under an atmospheric environment with relative humidity (RH) below 90% to prepare one highquality CsPbIBr 2 thick film with high crystallinity, excellent contact, and stable structure. We hope that our findings can help fabricate lowcost, highperformance, and longlasting photodiodetype CsPbIBr 2 photodetectors under an atmospheric environment.