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Improving the separation efficiency of photoinduced electron−hole pairs plays a vital role in preparing highperformance photocatalysts. Here, based on the good light corrosion resistance and excellent visible light response of Zn 0.5 Cd 0.5 S, as well as the unique catalytic, optical, and electrical properties of CeVO 4 , we tightly loaded CeVO 4 on Zn 0.5 Cd 0.5 S 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 Zn 0.5 Cd 0.5 S and CeVO 4 effectively inhibited the serious aggregation of Zn 0.5 Cd 0.5 S, which is conducive to the generation of active sites. On the other hand, an S-scheme heterojunction at the contact interface of Zn 0.5 Cd 0.5 S and CeVO 4 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 Zn 0.5 Cd 0.5 S/CeVO 4 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.

At present, inefficient charge separation of single photocatalyst impedes the development of photocatalytic hydrogen evolution. In this work, the CoS X /NiCo-LDH coreshell co-catalyst was cleverly designed, which exhibit high activity and high stability of hydrogen evolution in anhydrous ethanol system when coupled with CdS. Under visible light (λ � 420 nm) irradiation, the 3 %Co/NiCo/CdS composite photocatalyst exhibits a surprisingly high photocatalytic hydrogen evolution rate of 20.67 mmol g À 1 h À 1 , which is 59 times than that of the original CdS. Continuous light for 20 h still showed good cycle stability. In addition, the 3 %Co/NiCo/CdS composite catalyst also shows good hydrogen evolution performance under the Na 2 S/Na 2 SO 3 and lactic acid system. The fluorescence (PL), ultraviolet-visible diffuse reflectance (UV-vis) and photoelectrochemical tests show that the coupling of CdS and CoS X /NiCo-LDH not only accelerates the effective transfer of charges, but also greatly increases the absorption range of CdS to visible light. Therefore, the hydrogen evolution activity of the composite photocatalyst has been significantly improved. This work will provide new insights for the construction of new co-catalysts and the development of composite catalysts for hydrogen evolution in multiple systems.