Regular Article

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

¹ School of Science, Tianjin University of Technology and Education, Tianjin 300222, P.R. China
² School of Science, Tianjin University of Technology, Tianjin 300384, P.R. China

^* e-mail: shbshi@163.com

Received: 9 August 2022
Received in final form: 25 November 2022
Accepted: 29 November 2022
Published online: 26 December 2022

Abstract

The heterojunction ultraviolet photodetectors (UV PDs) were fabricated by growing NiO nanosheets on TiO₂ nanorod arrays (NRs) via hydrothermal method and their UV photoresponse properties were examined. The crystal structure, and optical properties of heterojunction were characterized by X-ray diffraction (XRD), Raman, absorption and photoluminescence (PL) spectra. The results of X-ray photoelectron spectroscopy (XPS) valence band (VB) spectrum, Mott–Schottky (M–S) curves and electrochemical impedance spectroscopy (EIS) of heterojunctions reveal the separation and transfer of photo-generated carriers in heterojunction interface. The UV PDs exhibit a large responsivity of 0.54 A/W and a high detection sensitivity of 6.0 × 10¹² Jones under 365 nm UV illumination at zero bias.