Enhanced photocatalytic activity and structural stability by hybridizing Ag3PO4 nanospheres with graphene oxide sheets

Abstract

Graphene oxide (GO)–Ag₃PO₄ nanocomposites synthesized through a facile solution approach via electrostatic interaction were investigated as excellent photocatalysts for the degradation of rhodamine B (RhB) under visible light irradiation. SEM and TEM observations indicate that Ag₃PO₄ nanospheres of ∼120 nm in diameter were well dispersed and anchored onto the exfoliated GO sheets. The characterizations of FTIR and Raman demonstrated the existence of strong charge interactions between GO sheets and Ag₃PO₄ nanospheres. As compared to Ag₃PO₄ nanospheres alone, the attachments of GO sheets led to a band gap narrowing (2.10 eV) and a strong absorbance in the near infrared region (NIR). The photoluminescence (PL) analysis indicates a more efficient separation of electron–hole pairs in the GO–Ag₃PO₄ nanocomposites. Notably, the incorporation of GO sheets not only significantly enhances the photocatalytic activity but also improves the structural stability of Ag₃PO₄. The positive synergistic effects between Ag₃PO₄ nanospheres and GO sheets are proposed to contribute to the improved photocatalytic properties. A possible photocatalytic mechanism of the GO–Ag₃PO₄ nanocomposites was assumed as well. The integration of these advantages enables such GO–Ag₃PO₄ hybrid material to be a nice photocatalyst for broad applications in a sewage treatment system.