Mo-W₁₈O₄₉/ZnIn₂S₄ Composites Synthesized by Metal Doping for Photocatalytic Hydrogen Evolution

Utilizing two or more semiconductor materials with distinct geometric and electronic energy arrangements at the nanoscale to construct heterostructures is an important means for developing high-performance catalysts for photocatalytic hydrogen evolution. In this study, ZnIn₂S₄ serves as the primary catalyst carrier, while Mo-W₁₈O₄₉ functions as the cocatalyst supported on the surface of ZnIn₂S₄. A series of ZnIn₂S₄/Mo-W₁₈O₄₉ heterojunction composite materials were synthesized through a straightforward hydrothermal method. The ZnIn₂S₄/Mo-W₁₈O₄₉ photocatalyst demonstrates exceptional photocatalytic hydrogen evolution activity. Notably, with a Mo-W₁₈O₄₉ loading of 10%, the photocatalyst achieves optimal hydrogen evolution, yielding 2592.8 μmol g^-1, which is 31 times greater than that of pure ZnIn₂S₄. Further characterized results of the samples showed that loading Mo-W₁₈O₄₉ with an appropriate mass ratio on ZnIn₂S₄ can increase the electron transfer rate, which facilitates reducing the recombination probability of photo-generated electrons and holes, thus improving hydrogen evolution efficiency.