Preparation and deep-ultraviolet photoelectric properties of Ga₂O₃ nanorod arrays/CuGaO₂ nanosheets composite films

Ga₂O₃ has been considered as an important wide bandgap semiconductor with prospective applications in deep ultraviolet (DUV) detectors and optoelectronic devices. In this paper, self-powered DUV photoelectric composite films have been prepared using α and β phases of Ga₂O₃ nanorod arrays (NRAs) composited with p-CuGaO₂ nanosheets (NSs). The structure, morphology, optical and photoelectric properties of the samples were systematically investigated. By constructing p-n junctions, the photoelectric performance of the composite films can be enhanced significantly. The highest photocurrent densities of α-Ga₂O₃ NRAs/CuGaO₂ NSs and β-Ga₂O₃ NRAs/CuGaO₂ NSs composite films can be obtained as 673.5 pA/cm² and 11.31 nA/cm² at 25 V, which are 8.7-fold and 8.3-fold higher than those of bare α-Ga₂O₃ and β-Ga₂O₃ films. The photoelectric response times of α-Ga₂O₃ NRAs/CuGaO₂ NSs and β-Ga₂O₃ NRAs/CuGaO₂ NSs composite films can be as fast as 0.18 and 0.07 s, better than most similar materials, demonstrating their bright prospect as sensitive photodetectors. This work offers a new perspective for the development of high-performance self-powered DUV detectors with p-n heterojunctions.