Surface passivation of CsPbBr3 films by interface engineering in efficient and stable self-powered perovskite photodetector

All-inorganic metal halide perovskite is considered as one of the most promising perovskite materials for photodetectors, because of its remarkable optoelectronic characteristics and stability. Whereas, it remains challenge to achieve both excellent photodetection performance and stability due to the multitudes of defects in perovskite films. Herein, an interface engineering based on surface passivation strategy to achieve high-quality CsPbBr3 perovskite films by introducing thioacetamide (C2H5NS, abbreviated as TAA) as interface materials is reported. The interaction between TAA and perovskite passivates the uncoordinated Pb2+ on the surface of CsPbBr3 film, suppress carrier non-recombination and accelerates carriers transfer. The self-powered photodetector based on the passivated CsPbBr3 film prefers the maximum responsivity of 0.26 A W−1 and detectivity of 8.39 × 1012 Jones under 520 nm irradiation. In addition, the optimized photodetector exhibits excellent stability and maintains more than 98% of its initial photocurrent when operating over 8 h. This work demonstrates an alternative approach for the preparation of improved performance in CsPbBr3 perovskite photodetectors and associated photoelectric devices.