Reduced graphene oxide/CdS for efficiently photocatalystic degradation of methylene blue

Abstract

Reduced graphene oxide/cadmium sulfide (RGO/CdS) hybrid material was synthesized by a one-step solvothermal method, wherein graphene oxide (GO) was a supporting material on which CdS nanoparticles were distributed homogeneously, and cadmium acetate (Cd(Ac)2·2H2O) was used as the CdS precursor. The supporting material RGO for CdS nanoparticles effectively enhanced their photocatalytic activities for the photodegradation of methylene blue in the aqueous solution. The optimum weight ratio of the GO to CdS in the hybrid material was 5.0%, which exhibited an excellent photodegradation efficiency (94%) and a better removal efficiency of total organic carbon (TOC) (57%), about 2.5 times and 5.1 times higher than that of pure CdS nanoparticles, respectively, under visible light (VL) irradiation. This improved photodegradation efficiency could be attributed to the increased adsorbability for methylene blue molecules, light absorption levels located in visible region, high charge transfer and separation ability, due to the introduction of a two-dimensional RGO network.