Ag3PO4/TiO2 composite for efficient photodegradation of organic pollutants under visible light

Abstract

Photocatalytic degradation of organic pollutants attracts much attention in environment remediation, and it is still a challenge to develop highly efficient and stable visible-light-response photocatalyst. Herein, we synthesized Ag3PO4/TiO2 (P-25) composite via a facile in situ precipitation method to enhance the activity and stability of Ag3PO4. SEM and TEM characterizations indicate TiO2 particles are dispersed on Ag3PO4 surface, resulting in heterojunction interfaces. UV–vis DRS spectra show that TiO2 in the composite does not interfere the absorption of visible light, while the photoluminescence spectra confirm TiO2 inhibits the recombination of photo-induced charges. Therefore, during the photodegradation of organic pollutants under visible light, the composites are much more active than pure Ag3PO4. Moreover, XPS and XRD analysis show the reduction of Ag3PO4 to Ag0 is retarded during the photoreaction. Furthermore, the effect of TiO2 amount in the composites was studied, and AP12 is the most active with the reaction rate being 1.43 times higher than pure Ag3PO4. The strategy of using TiO2 as activity and stability promoter to construct the composite may be useful in developing highly active and stable visible-light photocatalyst for pollutants removal.