NiS2/CdS photocatalysts with high specific surface area and excellent H2 evolution performance

The design and development of efficient photocatalyst is the key to raising the efficiency of H2 production via photocatalytic water-splitting. Herein, NiS2/H2O2–CdS (NC) composite photocatalysts were prepared by modifying CdS with H2O2 and using NiS2 as the cocatalyst. The experimental results showed that NC had excellent H2 evolution activity (42.21 mmol g−1 h−1), 136.2 times that of pure CdS, 3.8 times that of Pt/CdS (11.24 mmol g−1 h−1). Based on the detailed experimental characterization and DFT calculations, the excellent photocatalytic activity was discovered. Firstly, H2O2 changes the morphology of CdS from cone shape to mesoporous particles and greatly increases its specific surface area and also improves the diffusion of H2. Secondly, the cocatalyst NiS2 extends the range of light absorption, more importantly, it makes both the migration of electrons and reduction of H+/H3O+ much easier because it is metallic and of low absorption/desorption Gibbs energy for hydrogen.