Enhanced performance of solution-processed all-inorganic halide perovskite photodetectors by using bulk heterojunction and lateral configuration

Currently, all-inorganic halide perovskites are widely investigated for their applications in optoelectronics due to their excellent physical and chemical properties. In this paper, solution-processed bulk-heterojunction lateral photodetectors Ag/CsPbBr3:ZnO/Ag were built to enhance device performance, in which the active CsPbBr3 layer were surface-passivated by ZnO nanoparticles (NPs) in an optimized molar ratio. By optimizing the molar ratio of CsPbBr3 to ZnO NPs (i.e. kR=MCsPbBr3/MZnO), the photocurrent from the lateral photodetector was greatly enhanced and, the dark current was suppressed to as low as 10-12 A due to the lateral configuration by employing a 50 pm-width active layer made through an interdigital mask. As a result, the On/Off current ratio of the lateral photodetector Ag/CsPbBr3:ZnO/Ag reaches to more than 103 for an optimum molar ratio kR= 1:1, and it is 300-folds higher than that of the control device Ag/CsPbBr3/Ag, showing a maximum specific detectivity D* of 1.6 x 1011 Jones with a photoresponsivity of 3.8 mA/W under 16 pW/cm2 405 nm illumination at - 5 V. In this way, it provides an efficient method for solution-processed high-performance photodetectors by combining bulk heterojunction and lateral configuration. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

By optimizing the molar ratio of CsPbBr3 to ZnO NPs, the photocurrent of the lateral photodetector was greatly enhanced and dark current was suppressed, achieving a maximum specific detectivity D* of 1.6 x 1011 Jones with a photoresponsivity of 3.8 mA/W under 16 pW/cm2 405 nm illumination at -5 V. This study provides an efficient method for solution-processed high-performance photodetectors by combining bulk heterojunction and lateral configuration.