Metal element doping is an effective way to tune visible light absorption ability and improve the charge carrier separation efficiency of a semiconductor. Herein, we studied the visible light photoelectrocatalytic property of ZnO doped with nickel (Ni-ZnO). The Ni-ZnO film was prepared by using a liquid phase deposition technique. Scanning electron microscopy analysis and X-ray diffraction measurement indicated that the as-prepared Ni-ZnO film comprised of many prismatic wurtzite nanoparticles. X-ray photoelectron spectroscopy analysis indicated that Ni2+ entered the ZnO lattice. Cyclic voltammetric analysis confirmed that Ni2+ in the ZnO lattice was electroactive and a pair of Ni2+/Ni3+ redox waves were observed. UV-visible diffuse reflectance and photoluminescence spectra showed that doping of Ni in ZnO improved the visible light utilization and separation of photogenerated charge carriers. The Ni-ZnO film subsequently exhibited a higher photocurrent than the ZnO film. The photoelectrocatalytic activity of the Ni-ZnO film was evaluated by the degradation of tetracycline under visible light illumination. The degradation rate constant for tetracycline on Ni-ZnO film was found to be 1.65 times higher than that of ZnO film. (C) 2019 The Electrochemical Society.