Thin MAPb0.5Sn0.5I3 Perovskite Single Crystals for Sensitive Infrared Light Detection

Metal halide perovskite single-crystal detectors have attracted increasing attention due to the advantages of low noise, high sensitivity, and fast response. However, the narrow photoresponse range of widely investigated lead-based perovskite single crystals limit their application in near-infrared (NIR) detection. In this work, tin (Sn) is incorporated into methylammonium lead iodide (MAPbI(3)) single crystals to extend the absorption range to around 950 nm. Using a space-confined strategy, MAPb(0.5)Sn(0.5)I(3) single-crystal thin films with a thickness of 15 mu m is obtained, which is applied for sensitive NIR detection. The as-fabricated detectors show a responsivity of 0.514 A/W and a specific detectivity of 1.4974x10(11) cmHz(1/2)/W under 905 nm light illumination and -1V. Moreover, the NIR detectors exhibit good operational stability (similar to 30000 s), which can be attributed to the low trap density and good stability of perovskite single crystals. This work demonstrates an effective way for sensitive NIR detection.