Electrodeposition of Cu-doped p-type ZnO nanorods; effect of Cu doping on structural, optical and photoelectrocatalytic property of ZnO nanostructure

Abstract

p-type Cu-doped ZnO nanorods (Cu/ZnO NRs) were electrodeposited on F-doped tin oxide (FTO) substrates at low temperature and the effect of Cu doping on the structural, morphologic, conductivity, optical and photoelectrocatalytic properties of ZnO NRs were systematically investigated. XRD patterns shows all samples growth along c-axis perpendicular to the plane of the glass substrate and Cu2+ ions substituted with Zn2+ ions and did not changed the hexagonal wurtzite structure of the ZnO nanorods. SEM images shows pure and Cu-doped ZnO NRs vertically well–aligned throughout the substrate surface with a hexagonal shape which had an average diameter around 100–150 nm. UV–visible experiments show optical band gap of ZnO NRs decrease by Cu doping. Mott-Schottky analysis reveals that Cu doping induce p-type conductivity in ZnO NRs with high hole density. EIS and voltammetry analysis indicate that Cu doping effectively increased electron-hole separation under visible light and enhance photoelectrocatalytic property of ZnO NRs toward CO2 reduction.