32.2: Invited Paper: Embedding PbS Quantum Dots (QDs) in MAPbCl_0.5Br_2.5 Perovskite Single Crystal for Near‐infrared Detection

Abstract

Organometal lead‐halide perovskites demonstrate excellent photovoltaic performance in the visible (Vis) region. However, their lack of response in the near‐infrared (NIR) region limits their applications in broadband photodetectors. Here, PbS Quantum Dots (QDs) were successfully embedded in MAPbCl0.5Br2.5 single crystal by solution‐processed epitaxial growth. Perovskites can effectively passivate QDs or act as efficient charge transporters. The mobility of MAPbCl0.5Br2.5 with 1 wt% PbS QDs crystal is about 85 cm2/(V‐S), which is similar to that of pure MAPbCl0.5Br2.5 single crystal. Meanwhile the composite crystal exhibited a broadband response wavelength from the Vis (625 nm) to the NIR (850 nm) with fast response times (τon/τoff = 6/9 ms and τon/τoff = 19/43 ms in the visible and NIR regions, respectively). These results suggest that we have obtained high‐quality composite crystals.