One-pot synthesis of AgCl@Ag hybrid photocatalyst with high photocatalytic activity and photostability under visible light and sunlight irradiation

In this work, a highly efficient and stable AgCl@Ag hybrid photocatalyst was successfully prepared via a simple one-pot method at low temperature. X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and UV-Vis diffuse reflectance spectroscopy (DRS) were employed to characterize the as-prepared AgCl@Ag composite. The photocatalytic activity of the as-prepared AgCl@Ag was evaluated by the photodecoloration/photodegradation of some model organic pollutants, methyl orange (MO), methylene blue (MB), rhodamine B (RhB) and 4-nitrophenol. It was found that the as-prepared AgCl@Ag exhibited high photocatalytic activity and excellent photostability not only under visible light, but also sunlight irradiation. Kinetic studies by using active species scavenger technology suggested that hydroxyl radicals (OH) was not the dominant photooxidant, while holes (h(+)) and superoxide anion radicals (O-2(.-)) generated in the photocatalytic process played key roles in MO decoloration. A possible mechanism for the charge separation and MO photodecoloration is proposed. (C) 2014 Elsevier B.V. All rights reserved.