Fabricate Globular Flower-like CuS/CdIn2S4/ZnIn2S4 with High Visible Light Response via Microwave-assisted One-step Method and Its Multipathway Photoelectron Migration Properties for Hydrogen Evolution and Pollutant Degradation

The photocatalyst CuS/CdIn2S4/ZnIn2S4 with attractive visible light absorption was prepared by a microwave -assisted one-step method and then characterized by XRD, XPS, UV-vis/DRS, N-2 adsorption-desorption, SEM, TEM, and HRTEM tests. The results show that there are two kinds of crystal structures, hexagonal and cubic phase, in the product. Moreover, the composite has an absorption edge as high as 670 nm with a high visible light response. In addition, the composite possesses an excellent surface area of 239.3 m(2)/g, displays a favorable globular flower-like surface morphology, and consists mostly of three disparate shapes of crystals in the microstructure. Compared to heterogeneous ZnIn2S4 and P25, as-prepared composite demonstrates the greatest photocatalytic activity under simulated sunlight and visible light by methyl orange degradation. Together with Pt loading as a cocatalyst, hydrogen was achieved over CuS/CdIn2S4/ZnIn2S4 in Na2S-Na2SO3 aqueous solution, leading to a hydrogen production rate of 358.4 mu mol.h(-1).g(-1) under simulated sunlight and a high hydrogen production rate of 233.9 mu mol.h(-1).g(-1) under visible light (lambda > 420 nm). Additionally, the related formulas were utilized to calculate the semiconductor energy band configuration and speculate on the possible photoreaction mechanism of CuS/CdIn2S4/ZnIn2S4. Finally, the effect of multipathway photoinduced charge migration during photocatalysis process was explained.