Simple fabrication ZnO/β-Ga₂O₃ core/shell nanorod arrays and their photoresponse properties

In this paper, a facile and cost effective hydrothermal method was employed to fabricate high performance ZnO/β-Ga2O3 core-shell heterostructures. A highly sensitive ultraviolet (UV) sensor was fabricated based on vertically aligned β-Ga2O3 decorated ZnO core-shell nanorod arrays (NRs). The ZnO/β-Ga2O3 heterostructures showed an excellent improvement in UV response characteristics comparing with bare ZnO NRs. It can be attributed to the lower interface barrier and larger surface area-to-volume ratio for the ZnO/β-Ga2O3 heterostructures. Meanwhile, a higher concentration of surface oxygen vacancies has been observed in ZnO/β-Ga2O3 heterostructures, which helps to increase the charge separation efficiency for the UV detector. The results suggested that the ZnO/β-Ga2O3 core-shell heterostructure should be suitable for practical applications of UV photodetectors.