AUTHOR=Wu Jinming , Zhang Yongqiang , Yang Shuang , Chen Zhaolai , Zhu Wei 

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

JOURNAL=Frontiers in Chemistry

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2021.821699

DOI=10.3389/fchem.2021.821699

ISSN=2296-2646

ABSTRACT=<p>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<sub>3</sub>) single crystals to extend the absorption range to around 950 nm. Using a space-confined strategy, MAPb<sub>0.5</sub>Sn<sub>0.5</sub>I<sub>3</sub> single-crystal thin films with a thickness of 15 μm 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 1.4974×10<sup>11</sup> cmHz<sup>1/2</sup>/W under 905 nm light illumination and –1V. Moreover, the NIR detectors exhibit good operational stability (∼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.</p>