Recent developments of two-dimensional graphene-based composites in visible-light photocatalysis for eliminating persistent organic pollutants from wastewater

Over the last decade, two-dimensional graphene (2D GR) has brought new impetus in environmental photocatalysis, mainly benefiting from their unique physicochemical and photoelectric structural properties. Numbers of researchers have spared no effort to utilize visible-light-induced GR-based composites as catalyst platform to generate reactive species in photocatalytic oxidation technology. Herein, a comprehensive overview is presented on recent achievements of the construction and water-related applications of these photocatalysts for persistent organic pollutants (POPs) removal. A brief introduction of synthesis strategies is introduced for GR and its derivatives. Roles of GR as supports, flexible substrates and co-catalysts in composites are specifically pointed out with experimental studies. Most importantly, shortcomings (e.g., fast carrier recombination and serious photocorrosion) appeared in visible light photocatalysis and relative solutions by using GR species are clearly investigated. Based on the current research status, special attention has been paid to their promising applications on removing typical POPs, such as phenols, antibiotics, pharmaceuticals and dyes. Also, challenges (e.g., biotoxicity) and prospects are discussed for future developments in this field. This paper enriches the knowledge to deeply understand the catalytic performances and mechanisms of GR-based photocatalysts, and bring better perspectives for researchers in this field.