Graphene oxide enwrapped Ag3PO4 composite: towards a highly efficient and stable visible-light-induced photocatalyst for water purification

Abstract

A novel graphene oxide (GO) enwrapped Ag₃PO₄ (GO–Ag₃PO₄) composite as a visible-light-induced photocatalyst has been fabricated through an ion-exchange method of CH₃COOAg and Na₂HPO₄ in the presence of GO sheets. Scanning electron microscope and X-ray diffraction analysis confirmed that Ag₃PO₄ particles have been enwrapped by GO sheets. The UV-vis spectra curve of the GO–Ag₃PO₄ composite showed strong absorbance in the visible light regions. The photocatalytic activity of the composite was evaluated by the degradation of organic dye (AO7) and phenol under visible-light irradiation. The results indicated that this novel GO–Ag₃PO₄ composite exhibited significantly higher photocatalytic activities and improved stability under visible-light irradiation, compared with bare Ag₃PO₄. Moreover, the GO–Ag₃PO₄ composite showed both excellent intrinsic antibacterial and visible-light-induced photocatalytic disinfection activities toward E. coli cells. The possible mechanism for the enhanced photocatalytic properties and antibacterial activity of the GO–Ag₃PO₄ composite was also discussed. Our finding paves a way to design highly efficient and stable visible-light-induced photocatalysts for the removal of organic pollutants and pathogenic bacteria for water purification.