This study represents a new way of using attractive graphitic carbon material graphene as an electron mediator in designing new and efficient systems prepared using WO3 and POMS for photodegradation reactions. WO3 is known as a visible-light-responsive photocatalyst; however, it has low activity for the photodegradation of organic substances in the absence of co-catalysts. Because the rate of Electron–hole recombination limits the efficiency of WO3. Graphene can enhance the photocatalytic activity of WO3 in two aspects, namely, electron transportation and adsorption. Otherwise, hetropolyacids (as denoted HPA) are a well-known acid and oxidative catalysts with unique photoelectrochemical properties, reversible multielectron electrochemical reactants and catalytic activity. Thus, the effect of HPA and the graphene as co-catalysts in the performance of the graphene-WO3-HPA was investigated. The synthesized photococatalysts were found to be highly active under the visible light for photocatalytic degradation of azo dyes. The prepared catalysts were characterized by physicochemical techniques such as FT-IR, XRD, EDX, TEM, AFM, TG, BET, DRS, and SEM. This strategy can open up new avenues close to green chemistry achievements for studying the degradation of organic pollutants, including azo dyes.
