Facile assembly of CdS-reduced graphene oxide heterojunction with enhanced elimination performance for organic pollutants in wastewater

Heterojunction of cadmium sulfide (CdS) nanospheres and reduced graphene oxide (RGO) is performed by using an ice crystal template method combined with a freeze drying-calcination process. The resultant CdS-RGO with hierarchal porous structure possesses strong light absorption visible region and has higher specific surface area than the pristine CdS. Eventually, it exhibits much better adsorptivity and higher visible light-derived photocatalytic activity than the pristine CdS and RGO for eliminating organic pollutants in wastewater. The corresponding total removal efficiencies for rhodamine B (RhB) dyes and acid chrome blue K (AcbK) dyes are 97.2% and 65.7% under the present conditions, respectively. Remarkably, the heterojunction demonstrates excellent light corrosion resistance and superior reusability. The relative removal efficiency only loss 1.8% in the 4th run in comparison of that of the 1st run over the resultant CdS-RGO heterojunction. The results confirm the resultant heterojunction with high efficiency to be applied in elimination of organic pollutants in wastewater.