【Domestic Papers】β-Ga₂O₃ nanotube arrays for high-performance self-powered ultraviolet photoelectrochemical photodetectors

      Researchers from the Nanjing University have published a dissertation titled "β-Ga₂O₃ nanotube arrays for high-performance self-powered ultraviolet photoelectrochemical photodetectors " in Nanotechnology.

Abstract

      Self-powered ultraviolet (UV) photodetectors (PDs) are critical for future energy-efficient optoelectronic systems due to their low energy consumption and high sensitivity. In this paper, the vertically aligned β-Ga₂O₃ nanotube arrays (NTs) have been prepared on GaN/sapphire substrate by the thermal oxidation process combined with the dry etching technology, and applied in the UV photoelectrochemical photodetectors (PEC-PDs) for the first time. Based on the large specific surface area of β-Ga₂O₃ NTs on GaN/sapphire substrates and the solid/liquid heterojunction, the PEC-PDs exhibit excellent self-powered characteristics under 255 nm (UVA) and 365 nm (UVC) light illumination. Under 255 nm (365 nm) light illumination, the maximum responsivity of 49.9 mA/W (32.04 mA/W) and a high detectivity of 1.58×10¹¹ Jones (1.01×10¹¹ Jones) were achieved for the β-Ga₂O₃ NTs photodetectors at 0 V bias. In addition, the device shows a fast rise/decay time of 8/4 ms (4/2 ms), which is superior to the level of the previously reported self-powered UV PEC-PDs. This high-performance PEC-PD has potential applications in next-generation low-energy UV detection systems.

Paper Link：https://doi.org/10.1088/1361-6528/ad22a6