Photomultiplication-type perovskite photodetectors base on air-processed perovskite films

Perovskites have shown potential applications in low-cost and high-performance optoelectronic devices because of their solution processability and inherent outstanding optoelectronic properties. Among them, perovskite photodetectors have been the focus of scientific researches. Here, a photomultiplication-type perovskite photodetector is successfully fabricated with the high-quality perovskite films by spinning-bathing-spinning method in ambient air, which overcomes the stringent environmental requirement of the preparation of perovskite films. The photomultiplication photoconductive gain is realized by the traps-enhanced hole injection by capturing photogenerated electrons. The deep trap states provided by MoO3 capture the generated electrons in active layer, which causes the interfacial trap-assisted hole-tunneling injection, thus forming the gain. Consequently, the photomultiplication-type perovskite photodetector achieves a high external quantum efficiency over 52800% and exhibits a fast photoresponse time about 18.5 μs.