Amorphous W-S-P Modified ZnxCd1-xS with Tunable Band Structure for Efficient Photocatalytic Overall Water Splitting

The photocatalytic overall water splitting performance of the bandgap controllable ZnxCd1-xS solid solution is still restricted by its photo-corrosion. In this study, amorphous tungsten phosphosulphide (W-S-P) modified ZnxCd1-xS solid solution is successfully prepared as a visible-light-driven photocatalyst and an efficient and stable ZnxCd1-xS/W-S-P heterojunction is constructed through intimate W-S covalent bonds for efficient photocatalytic overall water splitting. The hydrogen evolution rate of the composite catalyst reached 18899.6 mu mol g(-1) h(-1), which is 86 times and 5 times higher than that of W-S-P and Zn0.5Cd0.5S, respectively. At this time, the precipitation rates of H-2 and O-2 were 157.07 mu mol g(-1) h(-1) and 78.05 mu mol g(-1) h(-1) without any noble metal catalyst. In this work, the overall water splitting efficiency of the catalyst is greatly improved by constructing a ZnxCd1-xS/W-S-P Schottky heterojunction, which further inhibits the photo-corrosion of the ZnxCd1-xS catalyst. At the same time, the strong internal electric field greatly improves the charge transfer efficiency. It provides a new idea for an in-depth understanding of the chemical changes of elemental binding energy in ZnxCd1-xS solid solution and the design of new binary photocatalytic materials.