Effective passivation via additive engineering based on CsPbBr3 films photodetectors and image sensor application

Abstract

All-inorganic perovskite photodetectors aroused widespread attention due to the splendid photoelectric characteristics and stability. However, the inherent defects in perovskite films hinders the progress of the photodetectors. Here, a Lewis base of thioacetamide additive was used to passivate defects in CsPbBr3 perovskite films based on Lewis acid-base interactions. The quality of the film has been distinctly enhanced due to the interaction between the S donor in thioacetamide and the uncoordinated Pb2+ in perovskite, diminishing the defect state density and inhibits the non-radiative recombination. The self-powered champion device based on CsPbBr3 film contain optimum thioacetamide additive exhibits a lower dark current density of 4.01 nA/cm2, a peak responsivity of 0.39 A/W, a rapid rise/decay time of 12.4 μs/56.2 μs, a peak detectivity of 1.08 × 1013 Jones and a lager linear dynamic range of 99 dB, which are much better than photodetector based on CsPbBr3 perovskite without TAA additive. Furthermore, it exhibits high-resolution imaging sensing capability at zero bias. This research affords guidance for the performance improvement and application of all-inorganic perovskite photodetectors.