Insight into the enhanced photocatalytic performance of Ag3PO4 modified metastable hexagonal WO3

A metastable hexagonal WO3 (h-WO3) was prepared by a hydrothermal reduction method with glycerol and the Ag3PO4/h-WO3 composites were synthesized via a precipitation method. Several techniques were employed to characterize the Ag3PO4/h-WO3 composites. Compared to the Ag3PO4/WO3 photocatalysts, the Ag3PO4/h-WO3 photocatalysts exhibited an excellent visible light photocatalytic performance for efficient degradation of methyl orange (MO). The analysis results showed that the favorable photocatalytic performance of the Ag3PO4/h-WO3 composites were mainly attributed to the h(+) and % O-2(-) generated during the recycles of W6+ and W5+. Furthermore, under the same conditions, the Ag3PO4/h-WO3 composites showed better stability than pure Ag3PO4 photocatalyst for degradation of MO, indicating that h-WO3 played an important role in the process of degradation. Based on the results of trapping experiments and XPS characterization analysis, the photocatalytic mechanism of the Ag3PO4/h-WO3 composites were proposed.