AgCl/Ag₃PO₄: A stable Ag-Based nanocomposite photocatalyst with enhanced photocatalytic activity for the degradation of parabens

An AgCl/Ag₃PO₄ composite has been successfully fabricated by a simple desorption–precipitation method. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV/Vis), and photoluminescence (PL) have been used to study the structural and physicochemical characteristics of the AgCl/Ag₃PO₄ composite. The photocatalytic activity of the AgCl/Ag₃PO₄ composite has been tested by the degradation of parabens under visible-light irradiation. 100% of MPB was degraded within 40 min in the AgCl/Ag₃PO₄-visible light system. Moreover, the photocatalytic activity of AgCl/Ag₃PO₄ remained at 94% of the original level after five runs, which was much higher than that of pure Ag₃PO₄ (25%). The obtained results confirmed that the AgCl/Ag₃PO₄ composite exhibited significantly higher photocatalytic performance and improved stability compared with bare Ag₃PO₄. The enhanced photocatalytic performance of the AgCl/Ag₃PO₄ composite could be mainly attributed to highly efficient charge separation through a synergistic effect of AgCl, Ag₃PO₄, and in situ photo-reduced Ag nanoparticles. Trapping experiments confirmed h⁺ and ·O₂⁻ to be the two main active species in the photocatalytic process. Finally, a possible photocatalytic mechanism for the charge-transfer process is proposed to account for the enhanced photocatalytic performance of the AgCl/Ag₃PO₄ composite.