Synergistic Effect of Bimetallic Sulfide Enhances the Performance of CdS Photocatalytic Hydrogen Evolution

High photogenerated electron-hole recombination rates and insufficient light absorption capacity are the main factors restricting the development of photocatalytic hydrogen evolution. CdS as a potential photocatalyst also faces these problems. In this work, the composite bimetallic sulfide ZnCo2S4 and CdS exhibits excellent photocatalytic hydrogen evolution capability. The synergistic effect of zinc ions and cobalt ions enriches the redox-active sites, which provides favorable conditions for the photocatalytic hydrogen evolution reaction. The synergistic effect of bimetallic ions as the main driving force for the accelerated hydrogen precipitation reaction is analyzed by fluorescence and electrochemical characterization. The results of hydrogen production experiments show that the hydrogen evolution amount of ZnCo2S4/CdS is about 10 times that of single CdS. In addition, the cyclic hydrogen production experiment and the structural characterization of the catalyst after hydrogen production proves that the catalyst has good stability. Last but not least, the apparent quantum efficiency of the composite catalyst with the best hydrogen evolution activity can reach 17.96%. This work provides a feasible method for expanding the application of CdS in the field of photocatalytic hydrogen evolution.

Automated summary

This research demonstrates the excellent photocatalytic hydrogen evolution capability of a composite bimetallic sulfide ZnCo2S4 and CdS. The synergistic effect of zinc ions and cobalt ions enriches the redox-active sites, improving the hydrogen production efficiency of the catalyst. The experimental results show that the hydrogen evolution amount of the composite catalyst is 10 times that of single CdS, and the catalyst exhibits good stability. The apparent quantum efficiency of the composite catalyst with the best hydrogen evolution activity reaches 17.96%. This work provides a feasible method for expanding the application of CdS in the field of photocatalytic hydrogen evolution.