WP modified the S-scheme Zn0.5Cd0.5S/WO3 for efficient photocatalytic hydrogen production
In this work, a noble metal free photocatalyst WP/Zn0.5Cd0.5S/WO3 (WZP) was prepared for the first time by simple hydrothermal and physical mixing methods. When the mass ratio of WP:Zn0.5Cd0.5S:WO3 reaches 0.4:1:0.4, the hydrogen production could reaches 26262 μmol within 5 h, which is about 5.04 times higher compared to pure Zn0.5Cd0.5S. WZP composite not only have good stability but excellent apparent quantum efficiency (6.19 %). The band gap and conduction band position of Zn0.5Cd0.5S and WO3 were identified by the results of UV-vis DRS and Mott-Schottky, and the existence of S-scheme between them was preliminarily determined. In addition to this, the existence of the S-scheme was further confirmed by the analysis of hydrogen evolution test results. A series characterization results such as UV-vis DRS, PL, TRPL and electrochemical showed that the addition of WP greatly improved the absorption and response of the composite to visible light. Base on the above experimental results, the possible hydrogen evolution mechanism of WZP photocatalyst was proposed. It is believed that this work marks an important step toward developing high-performance and low-cost photocatalytic materials for H2 evolution.