Fine control of Ce doped CH3NH3PbBr3 to modulate photoluminescence and carrier characteristics for application in photoconductive photodetectors

Abstract

Metal halide perovskites have triggered numerous studies in the application of optoelectronic devices. In this work, we incorporated Ce³⁺ ions into the MAPbBr₃ perovskite to extend the photoluminescence spectrum from the green light region to red light region, which can be attributed to the dopant-induced self-trapped exciton (STE) emission. Furthermore, the non-equivalent substitution of Ce³⁺ ions for the Pb²⁺ ions can result in extra electrons, thus can change the type of dominant carriers and improve the carrier mobility. The MAPbBr₃:Ce based photodetector exhibited a broadband photodetection capability over a wide range from 340 nm to 650 nm. In addition, after doping Ce³⁺ ions, the maximum device responsivity, detectivity and external quantum efficiency were efficiently improved. These results provide a new approach to highly-efficient and broadband-detecting photoconductive photodetectors.