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

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.