Photodegradation of rhodamine B and methyl orange by Ag3PO4 catalyst under visible light irradiation

A visible-light-driven Ag 3 PO 4 catalyst was successfully synthesized by a facile ion-exchange route. The as-synthesized Ag 3 PO 4 was characterized by X-Ray diffraction (XRD), field-emission scanning electron microscopy, N 2 adsorption-desorption, UV-Vis diffuse reflectance spectroscopy and Fourier transform infrared spectroscopy . Under visible light irradiation , the Ag 3 PO 4 catalyst showed excellent photocatalytic activity for rhodamine (RhB) degradation, but was poor at degrading methyl orange (MO) because of lower adsorption of MO molecules onto the surface of the Ag 3 PO 4 . The photodegradation of RhB and MO was achieved by holes and O 2 •− radical attack in the Ag 3 PO 4 suspension. The photodegradation of MO over the Ag 3 PO 4 catalyst was greatly enhanced in the presence of RhB owing to greater production of O 2 •− radicals.