Highly stable hierarchical p-CuO/ZnO nanorod/nanobranch photoelectrode for efficient solar energy conversion

In this study, we demonstrated a facile fabrication of highly stable CuO/ZnO nanorod-nanobranch based photocathode for photoelectrochemical hydrogen generation. Primary CuO nanorods (serving as a trunk) were synthesized via direct thermal oxidation of Cu nanorods that were grown by a template assisted electrodeposition method. Secondary ZnO nanobranches were uniformly grown on the entire surface of CuO nanorods via hydrothermal method. The prepared CuO/ZnO nanorod-nanobranch photoelectrode demonstrated an extremely high stability of 90% during a long term stability measurement. Morphological, optical and electrochemical characterizations have been carried out in order to understand the effects of ZnO nanorod branches on the overall electrochemical performance of the electrode.