A facile method to synthesize two-dimensional CsPb2Br5 nano-/micro-sheets for high-performance solution-processed photodetectors

In this paper, a facile method to synthesize two-dimensional (2D) all-inorganic CsPb2Br5 nano-/microsheets at room temperature and their application as the active layer in solution-processed high-performance photodetectors are presented. The obtained CsPb2Br5 nano-/micro-sheets showed a photoluminescence emission peak at 522 nm with a narrow full-width-at-half-maximum of similar to 17 nm, showing its high color purity, and an absorption peak at 307 nm with a shoulder peak at 339 nm. Then, the obtained CsPb(2)Br(5 )nano-/micro-sheets were used as the active layer in photoconductive photodetector and a high specific detectivity of 1.0 x 10(12) Jones with a photoresponsivity of 0.02 A/W and an ultra-low dark current of similar to 10(-1)2 An under 16 mu W/cm(2) 405 nm illumination were obtained from photoconductive photodetector Au/CsPb2Br5(85 mu m)/Au. Further, the physical mechanism for the enhanced performance is discussed. Therefore, it provides a new method to suppress dark current for high-performance CsPb2Br5 photodetectors. (C) 2020 Elsevier B.V. All rights reserved.