Fabrication of Ag₃PO₄-graphene composites with highly efficient and stable visible light photocatalytic performance

A facile and effective hydrothermal method for the fabrication of the Ag₃PO₄-graphene (Ag₃PO₄-GR) visible light photocatalyst has been developed to improve the photocatalytic performance and stability of Ag₃PO₄, and also to reduce the high cost of Ag₃PO₄ for practical uses. The size and morphology of Ag₃PO₄ particles could be tailored by the electrostatically driven assembly of Ag⁺ on graphene oxide (GO) sheets and by the controlled growth of Ag₃PO₄ particles on the GO surface. The generation of Ag₃PO₄ and the transformation of GO to GR can be achieved simultaneously in the hydrothermal process. The improved photocatalytic activity of Ag₃PO₄-GR composites under visible light irradiation is attributed to high-surface-area GR sheets, enhanced absorption of organic dyes, and more efficient separation of photogenerated electron-hole pairs. The transfer of photogenerated electrons from the surface of Ag₃PO₄ to GR sheets also reduces the possibility of decomposing Ag⁺ to metallic Ag, suggesting an improved stability of recyclable Ag₃PO₄-GR composite photocatalyst. Moreover, with the advances in the large-scale production of high-quality GO, the use of GO as the starting material can also reduce the cost for the synthesis of Ag₃PO₄-based photocatalysts without weakening their photocatalytic activities.