Tuning the Carrier Transfer Behavior of Coaxial ZnO/ZnS/ZnIn2S4Nanorods with a Coherent Lattice Heterojunction Structure for Photoelectrochemical Water Oxidation

Abstract Serious degradation and the short photogenerated carrier lifetime for the wide‐bandgap semiconductor ZnO have become prominent issues that negatively affect photoelectrochemical (PEC) water splitting. Herein, a novel electron transport pathway was constructed by simple but effective coaxial growth of ZnO/ZnS/ZnIn 2 S 4 heterostructure nanoarrays to increase the carrier separation efficiency. This new photoanode fulfilled the requirements of both favorable band alignment and stability, achieving a stable photocurrent density of 1.146 mA cm −2 at 1.2 V RHE , which was approximately twice that of pristine ZnO. Detailed experimental studies revealed that the improved PEC activity was due to the lattice‐matching interface coherency that activated the carrier transport pathway, giving rise to an optimized interfacial electronic structure for promoted charge separation by the built‐in electric field and strengthened water oxidation activity. This design may provide a new approach to fabricating various efficient lattice‐matching coherent interface photoanodes for PEC water splitting.