Self-powered heterojunction ultraviolet photodetector based on NiO nanosheets/TiO2 nanorods

Abstract

NiO/TiO2 heterojunction devices were fabricated through growing NiO nanosheets by hydrothermal method on TiO2 NRs and their UV photoresponse properties were examined. The crystal structure, and optical properties of heterojunction is characterized by XRD, Raman spectrum, absorption and PL. The results of XPS valence band spectrum, M-S curves and EIS curves for NiO/TiO2 heterojunctions revealed that the separation and transfer of the photo-generated carriers occur in heterojunction interface. The heterojunction devices exhibit a large responsivity of 0.54 A/W and a high detection sensitivity of 6.0×1012 Jones under UV illumination with wavelength of 370 nm at zero bias.