Design and Preparation of a CeVO₄/Zn_0.5Cd_0.5S S-Scheme Heterojunction for Efficient Photocatalytic Hydrogen Evolution

Improving the separation efficiency of photoinduced electron–hole pairs plays a vital role in preparing high-performance photocatalysts. Here, based on the good light corrosion resistance and excellent visible light response of Zn0.5Cd0.5S, as well as the unique catalytic, optical, and electrical properties of CeVO4, we tightly loaded CeVO4 on Zn0.5Cd0.5S by physical coupling to overcome its severe photogenic carrier recombination and obtained a highly efficient photocatalytic catalyst for hydrogen evolution. One the one hand, the close coupling of Zn0.5Cd0.5S and CeVO4 effectively inhibited the serious aggregation of Zn0.5Cd0.5S, which is conducive to the generation of active sites. On the other hand, an S-scheme heterojunction at the contact interface of Zn0.5Cd0.5S and CeVO4 was successfully built. The formation of the S-scheme heterojunction could consume useless electrons and holes and enable the efficient use of photogenerated electrons to participate in the reaction of reducing water. Finally, the hydrogen yield of Zn0.5Cd0.5S/CeVO4 can reach 695.55 μmol in 5 h. Our work provided an idea for the rational design of heterojunction photocatalysts to obtain excellent hydrogen production performance.