CdS/Ag2S/g-C3N4 ternary composites with superior photocatalytic performance for hydrogen evolution under visible light irradiation

CdS/Ag2S/g-C3N4 ternary composites as photocatalysts with different amounts of Ag2S were successfully synthesized through a simple chemical deposition method. These photocatalysts were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) mapping and X-ray photoelectron spectroscopy (XPS) to obtain the information of the structure and composition. Compared with the pure samples and binary composites, CdS/Ag2S/g-C3N4 ternary composites showed enhanced hydrogen production activities, and the maximum hydrogen production rate of CdS/Ag2S(2%)/CN is about 1020.54 mu mol g(-1) h(-1) in Na2S-Na2SO3 solution. Based on the photoluminescence and electrochemical results, the improved photocatalytic activity could be attributed not only to the synergic effect of ternary components in the composite, but also to the introduction of Ag2S that provided abundant active sites for H-2 production. A possible mechanism was investigated in detail.

Automated summary

CdS/Ag2S/g-C3N4 ternary composites were successfully synthesized as photocatalysts using a simple chemical deposition method, and characterized by various analytical techniques. Compared to pure samples and binary composites, the ternary composites showed enhanced hydrogen production activities, attributed to the synergic effect of ternary components and the introduction of Ag2S providing abundant active sites for H2 production.