RGO-induced charge transfer and hole oxidation enhanced photocatalytic degradation and disinfection performance of novel ternary nanocomposite under visible light irradiation

Abstract

A novel graphene-bridged AgCl/Ag3PO4/rGO photocatalyst with admirable visible-light-driven photocatalytic performance was prepared through a combination of in-situ precipitation and anion-exchange method. The photocatalyst was revealed a well-defined heterostructure in which few-layers rGO sheets are decorated by AgCl and Ag3PO4 nanoparticles. The ternary photocatalyst exhibits excellent photocatalytic activity for the degradation of methylparaben (MPB) and the inactivation of Gram-negative Escherichia coli (E. coli) due to the synergistic effects of AgCl, Ag3PO4 and rGO. Results show that 20 mg•L−1 of MPB or 107 CFU•mL−1 of E. coli can be eliminated in AgCl/Ag3PO4/rGO system within 40 min under visible-light irradiation. Moreover, great stability and reusability were also observed for the ternary photocatalyst. Trapping experiments further confirm that h+ is the most important active specie, which indicates the importance of rGO due to its high electron transfer ability. And the possible photocatalytic mechanisms of AgCl/Ag3PO4/rGO in visible light system were finally proposed.