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

An AgCl/AgPO 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/AgPO composite. The photocatalytic activity of the AgCl/AgPO composite has been tested by the degradation of parabens under visible-light irradiation. 100% of MPB was degraded within 40 min in the AgCl/AgPO-visible light system. Moreover, the photocatalytic activity of AgCl/AgPO remained at 94% of the original level after five runs, which was much higher than that of pure AgPO (25%). The obtained results confirmed that the AgCl/AgPO composite exhibited significantly higher photocatalytic performance and improved stability compared with bare AgPO. The enhanced photocatalytic performance of the AgCl/AgPO composite could be mainly attributed to highly efficient charge separation through a synergistic effect of AgCl, AgPO, and in situ photo-reduced Ag nanoparticles. Trapping experiments confirmed h and ·O 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/AgPO composite.