Surfactant-assisted synthesis of highly dispersed ZnS(C) /BiOBr/GO ternary composites for effectively improve the degradation ability of organic pollutants under visible light

Abstract

In this paper, the highly dispersed ZnS(C)/BiOBr/ GO ternary composite was prepared by a two-step hydrothermal method with the help of the surfactant cetyltrimethyl ammonium bromide (CTAB). Its structure and morphology were studied by XRD, SEM, TEM, EDX spectra, UV–VIS absorption spectra, Mott-Schottky curve and Brunau-Emmett-Teller (BET) characterization. The results show that the ZnS(C)/BiOBr/GO ternary photocatalyst with excellent degradation effect and stable specific surface area has been successfully prepared. Orthogonal and photocatalytic experiments showed that the prepared photocatalyst had high photocatalytic performance for the degradation of brilliant blue (BB), Rhodamine B (RhB) and tetracycline hydrochloride (TCH). The degradation rate constants for BB, TCH and RhB were 0.12515, 0.06194 and 0.76750 min−1, respectively. Moreover, the photocatalytic performance of ZnS(C)/BiOBr/GO composite is significantly better than that of the original ZnS(C) and BiOBr. It is worth noting that ZnS(C)/BiOBr/GO ternary composite assisted by CTAB has the best photocatalytic activity, mainly for two reasons. First, the presence of surfactant CTAB significantly reduces the agglomeration of ZnS and enhances the dispersion of ZnS. Second, GO can be used as an electron trapping agent between ZnS and BiOBr to promote carrier separation. Therefore, the synthesis of ternary compounds with appropriate additional surfactants can effectively improve the photocatalytic efficiency of the degradation of organic pollutants. This study is expected to expand the application of surfactants in the preparation of semiconductor photocatalysts.