Enhanced visible light-driven photocatalytic performance and stability of Ag3PO4 by simultaneously loading AgCl and Fe(III)

Silver phosphate (Ag3PO4) is widely used in the field of photocatalysis due to its excellent quantum efficiency and high photocatalytic activity. With Ag3PO4 as the precursor, we have prepared a ternary composite of Ag3PO4/AgCl/Fe(III) through an in-situ anion-exchange and impregnation method by using ferric chloride as the sources of chlorine and iron. The characterization results indicated that AgCl and Fe(III) were successfully loaded onto the surface of Ag3PO4 without any changes in its morphology and crystal structure. A significantly enhanced photocatalytic performance for the degradation of tetracycline (TC) was obtained under visible light irradiation (> 420 nm). The degradation rate of TC over Ag3PO4/AgCl/Fe(III) (0.458 min(-1)) was 2.32 times and 2.94 times that of Ag3PO4/AgCl (0.197 min(-1)) and the pure Ag3PO4 (0.156 min(-1)), respectively. Furthermore, the stability of the photocatalyst was also improved. On one hand, the presence of AgCl could prevent Ag3PO4 from dissolution due to the smaller solubility of AgCl. On the other hand, the heterostructure and Fe(III) in Ag3PO4/AgCl/Fe(III) could promote the transfer and the separation of photoexcited electrons and holes, thus enhancing the photocatalytic activity. Our investigation might give some new insights for the facile preparation of photocatalysts with high visible light-driven photocatalytic performance.