The Multiple Promotion Effects of Ammonium Phosphate-Modified Ag₃PO₄ on Photocatalytic Performance

Phosphate ( $$ ) modification of semiconductor photocatalysts such as TiO₂, C₃N₄, BiVO₄, and etc. has been shown positive effect on the enhancement of photocatalytic performance. In the present study, we demonstrate a novel one-pot surface modification route on Ag₃PO₄ photocatalyst by ammonium phosphate [(NH₄)₃PO₄], which combines $$ modification with ammonium ( $$ ) etching to show multiple effects on the structural variation of Ag₃PO₄ samples. The modified Ag₃PO₄ photocatalysts exhibit much higher photocatalytic performance than bare Ag₃PO₄ for the degradation of organic dye solutions under visible light irradiation. It is indicated that the $$ etching favors the surface transition from Ag₃PO₄ to metallic Ag nanoparticles, resulting in the fast capture of photogenerated electrons and the followed generation of $$ radicals. The strongly adsorbed $$ on the Ag₃PO₄ surfaces can further provide more negative electrostatic field, which improves the separation of photogenerated electron-hole pairs by inducing the holes to directly flow to the surface and then enhances the formation of reactive ·OH radicals. Furthermore, the photocatalytic performance of the modified Ag₃PO₄ photocatalysts can be optimized by monitoring the concentration of (NH₄)₃PO₄ that is 1 mM.