Z scheme system ZnIn2S4/RGO/BiVO4 for hydrogen generation from water splitting and simultaneous degradation of organic pollutants under visible light

Abstract

The Z scheme system ZnIn2S4/RGO/BiVO4 was synthesized using the hydrothermal method. The activities of hydrogen generation from decomposition of water and the organic pollutants degradation have been evaluated under visible-light irradiation. The Z scheme system can catalyze the hydrogen generation from water splitting and organic pollutants degradation simultaneously under visible light. The presence of organic pollutants can promote the hydrogen generation from water splitting. The activity of hydrogen production is related to the reduction properties of the organic compounds and the highest hydrogen production efficiency obtained in the presence of formaldehyde. The hydrogen production rate, formaldehyde degradation rate, the A.Q.Y. and the ηc are determined to be 1687 μmol g−1 h−1, 22.2 mmol g−1 h−1, 22.9% and 13.3% when the formaldehyde concentration is 5 mol L−1, the concentration of the catalyst is 1.5 g L−1, the initial pH of solution is 13. When mixed organic pollutants are added, the system can also have a good activity for hydrogen production and organic pollutants degradation. Furthermore, the mechanism of the Z scheme system ZnIn2S4/RGO/BiVO4 for hydrogen generation and simultaneous degradation of organic pollutants has been also discussed.