Ag nanowires assisted CH3NH3PbBr3–ZnO heterostructure with fast negative photoconductive response

Abstract

Due to its attractive interaction with light, negative photoconductivity (NPC) has received widespread attention and has been used in optoelectronic logic devices with excellent performance. However, long negative response time triggered by photogenerated carriers trapping mechanism became a bottleneck in further application. Therefore, an enhanced strategy that can speed up negative response is urgently needed. Herein, we prepared a zinc oxide microwire (ZnO MW)–silver nanowires (Ag NWs)–methylammonium lead halide perovskite (CH3NH3PbBr3) heterostructure with enhanced negative response than the previous NPC device. The Ag NWs with high mobility at the interface of ZnO and CH3NH3PbBr3 accelerate the photoresponse time from 50 to 5.4 s and improve the dark current recovery time by two orders of magnitude. This work provides a strategy to improve the negative response speed with simple operation, which represents a step toward applications in the field of fast NPC optoelectronics.