【Device Papers】Construction of α-Ga₂O₃/Nb₂CTx heterojunction for self-powered photoelectrochemical solar-blind ultraviolet photodetectors

      Researchers from the Chongqing University of Arts and Sciences have published a dissertation titled "Construction of α-Ga₂O₃/Nb₂CT_x heterojunction for self-powered photoelectrochemical solar-blind ultraviolet photodetectors" in Materials Science in Semiconductor Processing.

Abstract

      Fabricating heterojunction between gallium oxide (Ga₂O₃) and other suitable materials is an effective way to improve the photoelectronic performance of photodetector. Herein, α-Ga₂O₃/Nb₂CT_x heterojunction has been constructed for self-powered photoelectrochemical (PEC) solar-blind ultraviolet (UV) photodetector. Under 254 nm UV light illumination and without external bias, the α-Ga₂O₃/Nb₂CT_x heterojunction photodetector exhibits enhanced photo-to-dark current ratio (58.1), responsivity (35.4 mA/W), and detectivity (2.6 × 10¹¹ Jones), which are 2.4, 2.1, and 2.2 times higher than those of pure α-Ga₂O₃ PEC photodetector. Furthermore, the α-Ga₂O₃/Nb₂CT_x heterojunction photodetector has rapid response speed (0.2 s/0.1 s) and excellent long-term stability. The enhanced photoelectric properties are attributed to the vertically aligned nanorod array structure of α-Ga₂O₃, the high carrier mobility and conductivity of Nb₂CT_x, and the built-in electric field established by the α-Ga₂O₃/Nb₂CT_x heterojunction, which can effectively facilitate the separation and direct transport of photogenerated carriers at the interface. The as-constructed α-Ga₂O₃/Nb₂CT_x heterojunction photodetector with outstanding photoelectric performance demonstrates promising application prospects in missile tracking, optical communication, and UV imaging, etc.

DOI：

https://doi.org/10.1016/j.mssp.2025.110201