Combination of ZnO and Cu2O semiconductors is remarkable for efficient photovoltaic cells and enhanced photoelectrochemical (PEC) performance due to the high electronic energy band alignment of these materials and their controllable electronic structure at the interface. This study reports on a systematic analysis of the effects of Cu2O nanocube doping on the structural properties and PEC performance of ZnO films. ZnO samples doped with Cu2O were prepared by a practical electrochemical method. Characterization of the materials was performed by XRD, Raman, FTIR spectroscopy and electrochemical techniques. The XRD, Raman, FTIR spectroscopy analyses indicated a single phase of ZnO for the lower Cu2O deposition time, while a secondary phase of Cu2O evolved for the 5 min deposition time. This study showed that ZnO doped with Cu2O grown for 3 min had the best PEC performance. ZnO/Cu2O photoelectrodes are recommended as an attractive, competitive and alternative candidate for advanced PEC sensing and this may be for the extended field of water splitting into oxygen and hydrogen under sunlight. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.