High Efficient Photodegradation and Photocatalytic Hydrogen Production of CdS/BiVO4 Heterostructure through Z-Scheme Process

Novel heterostructured CdS/BiVO4 nanocomposites were fabricated in a low-temperature water bath system. The uniform CdS nanoparticles with an average size of 20 nm were homogeneously interspersed on BiVO4 nanosheets. The coupling of BiVO4 and CdS nanoparticles could notably promote the photocatalytic activity. The composites reached a high H2-production rate of 0.57 mmol h–1 under visible light irradiation, about 5.18 times higher than that of pure CdS nanoparticles. The dominant active species in the photocatalytic system were also confirmed by the radical trapping test. Based on the calculation and experimental results, a Z-scheme photocatalytic mechanism was proposed, which was further confirmed by the electrochemical impedance spectroscopy and the cycling test. The Z-scheme photocatalytic system endows the CdS/BiVO4 heterostructure with strong reducibility and oxidizability and excellent stability.