【Device Papers】Self-powered CsPbIBr₂/Ga₂O₃ van der Waals heterojunction with high responsivity and large external quantum efficiency

      Researchers from Inner Mongolia University‌ and Lanzhou University of Technology‌ have published a dissertation titled " Self-powered CsPbIBr₂/Ga₂O₃van der Waals heterojunction with high responsivity and large external quantum efficiency " in 《物理学报》。

Abstract

      This article reports a self-powered deep ultraviolet (DUV) photodetector based on a CsPbIBr₂/Ga₂O₃ van der Waals heterojunction, which was fabricated through a combination of plasma-enhanced chemical vapor deposition (PECVD) and hot-casting. Characterization by X-ray diffraction and scanning electron microscopy confirmed the film quality of β-Ga₂O₃ and CsPbIBr₂. The optical bandgaps of Ga₂O₃ and CsPbIBr₂ were determined to be 4.75 eV and 2.03 eV, respectively, through the Tauc plot. According to Anderson's rule, the van der Waals heterojunction was confirmed to be a type II band alignment with a stable built-in electric field at the interface. The device exhibited an extremely low dark current density (2.09×10^-10 A/cm²) and a high light-dark current ratio of 4.01×10³ under a bias voltage of 10 V. Thanks to the built-in electric field at the interface, the detector achieved stable and repeatable photoresponse at zero bias voltage, demonstrating excellent self-powered capabilities. Under 254 nm DUV irradiation and a bias voltage of 10 V, the detector achieved a responsivity of 0.17 A/W, an external quantum efficiency of 85%, and a specific detectivity of 2.98×10¹² Jones. In summary, this study provides a reference path for high-performance self-powered solar-blind UV photodetection.

Link：

https://kns.cnki.net/kcms2/article/abstract?v=pX0ZfcSLBkWkzrwiPiisl90rQqmYrZ1bDKz9We_1uachcQOCd0_xsU1J0VGZRxQMFjhCfJOpPv6jAPBk724o7sA1GIAKSTeXegAj5OtqLFipKWc92n3TtHoVUA0ooZKPUSI-lB1TRxKIHL2RzA8vkCrgAOAMXoWbz6MuInPVbKkxTDjOR3s1Ag==&uniplatform=NZKPT&language=CHS