【Domestic Papers】Self-powered deep UV photodetector based on gallium oxide nanocrystals

      Recently, the research team of Prof. Chongxin Shan and Associate Prof. Xun Yang from Zhengzhou University and Qiao Qian from Zhejiang Ocean University cooperated to prepare zero-dimensional Ga₂O₃ nanocrystals (NCs) with high crystallinity by sol-gel method, as well as construct GaN/γ-Ga₂O₃ NCs heterojunction self-powered UV photodetectors by spin-coating technology. Under 254nm wavelength, 0.16 mW cm^-2 power density light exposure, the responsivity, detectivity, and external quantum efficiency of self-powered devices with a 300nm thick active layer can reach 6.7×10⁻³ A·W⁻¹, 3.10×10¹¹ Jones, and 3.2% respectively. Meanwhile, the high response and stability of the device show that it has potential UV imaging capabilities, which is also confirmed in the single-point imaging detection systems.

Abstract

      In this paper, the researchers successfully synthesized zero-dimensional colloidal nanocrystals (NCs) of high-crystallinity γ-phase gallium oxide (γ-Ga₂O₃) by sol-gel method, Subsequently, and then deposited of different thicknesses on p-type GaN substrate by spin-coating method, and then constructed a heterojunction photodetector. The detector exhibits self-powered capability through the photovoltaic effect under UV light. Notably, the response, detection and external quantum efficiency of self-powered device with a 300nm thick active layer can reach 6.7×10^-3 A·W^-1, 3.10×10¹¹ Jones, and 3.2% respectively, without the need for the external power source. Test results indicate that this photodetector has promising applications in single-point imaging systems. This paper proposes a simple preparation method for high-performance self-powered UV photodetector based on zero-dimensional γ-Ga₂O₃ nanoparticles, which opens up possibilities for the application of passive components and various photon systems.

DOI: 10.1021/acsnano.4c00090