Interface Engineering Ti3C2 MXene/Silicon Self‐Powered Photodetectors with High Responsivity and Detectivity for Weak Light Applications

• DOI: 10.1002/smll.202100439
• Publication Date: 2021-04-23T18:28:04Z
• Authors: Weidong Song; Qing Liu; Jiaxin Chen; Zhao Chen; Xin He; Qingguang Zeng; Shuti Li; Longfei He; Zhitao Chen; Xiaosheng Fang
• Keywords: Quantum Efficiency; Specific detectivity; Photoelectric effect; Photoconductivity

Abstract Interfacial engineering and heterostructures designing are two efficient routes to improve photoelectric characteristics of a photodetector. Herein, Ti 3 C 2 MXene/Si heterojunction photodetector with ultrahigh specific detectivity (2.03 × 10 13 Jones) remarkable responsivity (402 mA W −1 ) at zero external bias without decline as increasing the light power is reported. This achieved by chemically regrown interfacial SiO x layer control MXene thickness suppress dark noise current photoresponse. The demonstrates high on/off ratio over 6 , an outstanding peak quantum efficiency ( EQE 60.3%, while it maintains ultralow 0 V bias. Moreover, device holds performance 55% even after encapsulated silicone, trying resolve air stability issue MXene. Such detectivity, responsivity, self‐powered capability particularly applicable detect weak signal, which presents potential for imaging, communication sensing applications.