Negative Differential Resistance in the Au-Coated CH₃NH₃PbBr₃ Perovskite Photodetectors with Fast Response

Lead halide perovskites have emerged as attractive photoelectric materials owing to their excellent performance, which demonstrates great potential for application in the optoelectronic field. A basic understanding of the photogenerated carrier transport in perovskite photodetectors is critical to achieving high-performance devices. Here, we reported the ultraviolet photodetectors with a fast response based on the Au coated CH3NH3PbBr3 perovskite nanowires, which were grown by an in situ solution method. Interestingly, the devices exhibited negative differential resistance (NDR) behaviors at high power intensity, relevant to the ion migration in the nanowires. The carrier transport process and the state of energy band bending were discussed in detail. This work provides a valuable idea for designing fast-response photodetectors with the function of memristors.