Synthesis of ZnWO4/Ag3PO4 p–n heterojunction photocatalyst and enhanced visible-light photocatalytic applications

The ZnWO 4 /Ag 3 PO 4 nanocomposites synthesized by simple precipitation process were characterized by powder XRD, SEM, TEM, HRTEM and UV-vis diffuse reflectance spectra. The results indicated that the ZnWO 4 nanorods dispersed well on the surface of Ag 3 PO 4 particles and ball-and-rod structure p-n heterojunction was fabricated successfully. In subsequent degradation experiment of methyl orange (MO), ZnWO 4 /Ag 3 PO 4 composites showed the highest photocatalytic activity comparing to pure Ag 3 PO 4 and ZnWO 4 , due to the presence of ZnWO 4 /Ag 3 PO 4 heterojunctions, which could separate and transfer the electron–hole pairs generated by visible light and enhance the photocatalytic performance of catalysts. Furthermore, the band gap structure and degradation mechanism of the enhanced photocatalytic materials were discussed in this article. In conclusion, the ZnWO 4 /Ag 3 PO 4 composite was a promising and excellent photocatalyst for degradation of dye wastewater under visible light irradiation.