Preparation and Visible-Light Driven Photocatalytic Properties of CuS/Reduced Graphene Oxide Composites

The CuS/RGO composites were prepared using a facile one-step solvothermal method. The asobtained samples were characterized by X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Brunner-Emmet-Teller (BET) measurements and UV-Vis spectrophotometry. The results showed that the CuS particles were uniformly dispersed on the surface of RGO and electronic migration effect existed between RGO and CuS. The photocatalytic activity of CuS/RGO composites was evaluated by the degradation of Cationic blue SD-BL, Cationic red X-5GN, Direct blue 86, Reactive blue KN-R, Methylene blue and Rhodamine B under visible light irradiation. The photocatalytic experiments showed that the CuS/RGO composites exhibited a better photocatalytic performance for organic dyes with absence of hydrogen peroxide (H₂O₂) due to the inhibition of recombination of electron–hole pair induced on the surface of CuS. The photodegradation ratio of Cationic blue SD-BL, Cationic red X-5GN, Direct blue 86, Reactive blue KN-R, Methylene blue and Rhodamine B increased to 100%, 95.8%, 99.5%, 87.8%, 100%, 81% after 75 min of irradiation, respectively. Moreover, no significant decline of CuS/RGO photocatalyst for photodegradation of dyes was observed after five cycles, indicating better photostability of the samples. Thus, the CuS/RGO composites could have a promising application in wastewater treatment.