Regulation of ZnO/CuInS₂ Nanostructure and Improvement of Its Photocatalytic Hydrogen Production Performance

To address the constraints of CuInS₂ in photocatalytic applications, ZnO was synthesized using the sol–gel technique, along with the in-situ hydrothermal method to acquire the ZnO/CuInS₂ heterojunction photocatalyst. Comparisons with the pure CuInS₂ monomer revealed that the fabricated composites demonstrated significant improvement in photocatalytic hydrogen production under simulated sunlight exposures. The optimal hydrogen production rate reached approximately 31-fold that of CuInS₂ alone. The improved photocatalytic activity of ZnO/CuInS₂ can be attributed to the successful formation of the heterojunction, which facilitates the effective transfer of electrons induced by light at the interface. Moreover, the composite photocatalyst significantly reduces electron–hole recombination resulting in efficient conversion of light energy to electrical energy. This study improves the performance of photocatalytic hydrogen production performance in CuInS₂, providing a valuable reference for the development of photocatalytic hydrogen production catalysts.