Research progress on photocatalytic degradation of organic pollutants in wastewater by graphene-based composites

Abstract

Photocatalytic degradation is one of the fast and efficient methods for the treatment of organic pollutants in wastewater. Graphene-based composites, due to exceptional electronic conductivity, broad light absorption spectrum, large specific surface area, and high adsorption capacity, significantly enhance the photocatalytic activity when graphene was combined with metals, metal oxides, polymers, and other compounds, resulting in more efficient degradation of organic pollutants in wastewater. The review systematically outlined the primary synthesis methods of graphene-based composite materials and their applications in the removal of organic pollutants from wastewater. The enhancement of catalytic performance in semiconductor photocatalytic materials doped with graphene and the mechanisms of composite photocatalysts enhanced by graphene were discussed. The mechanisms involved enhancing adsorption of organic pollutants, accelerating electron transfer rates, and broadening the range and intensity of light absorption. Finally, the existing problems of graphene-based composites were analyzed, and the future development direction was pointed out.

Keywords

• graphene
• photocatalysis
• wastewater
• organic pollutants