Effect of ZnS buffer layers in ZnO/ZnS/CdS nanorod array photoelectrode on the photoelectrochemical performance

Abstract

ZnO/CdS/ZnS and ZnO/ZnS/CdS nanorod array photoelectrodes were constructed and fabricated by an alternative chemical bath deposition of CdS and ZnS layers onto the surface of the ZnO nanorod array. The photoelectrochemical performances of composite photoelectrodes were investigated, and the action mechanism of ZnS buffer layers was also considered. The results show that the ZnO/ZnS/CdS nanorod array photoelectrode possesses enhanced hydrogen production efficiency. The enhancement may be attributed to the ZnS buffer layers, which are advantageous in the separation and transportation of photogenerated electron–hole pairs in ZnO/ZnS/CdS nanorod array photoelectrodes.