Ag3PO4/graphene-oxide composite with remarkably enhanced visible-light-driven photocatalytic activity toward dyes in water

Ag3PO4/graphene-oxide (Ag3PO4/GO) composite has been synthesized by a liquid phase deposition method, and used for the photodegradation of organic dyes in water under visible light. The as-synthesized samples were characterized by X-ray diffraction, scanning electron microscope, N-2 sorption-desorption, and UV-vis diffuse reflectance spectra. The SEM image indicated that Ag3PO4 particles were mainly distributed on the surface of GO sheets uniformly. DRS analysis revealed that the samples had good visible light response. The photocatalytic activity of Ag3PO4/GO composite was evaluated by decomposing of dyes (such as methyl orange, rhodamine B) in water under visible or UV-vis light irradiation. The degradation results indicated that the photocatalytic performance of Ag3PO4/GO was greatly enhanced due to the improved adsorption performance and separation efficiency of photo-generated carriers. The Ag3PO4/GO composite with GO content of 15 wt.% exhibited superior activity under visible light irradiation. After 50 min of reaction, the degradation ratio of MO was about 86.7%, while RhB solution could be completely degraded within 30 min of reaction. Further study proved that the direct oxidation of pollutants by holes has played a major role in the degradation process. The results of this work would provide a new sight for the construction of visible light-responsive photocatalysts with high performance. (C) 2012 Elsevier B.V. All rights reserved.