Sonochemical fabrication, characterization and enhanced photocatalytic performance of Ag2S/Ag2WO4 composite microrods

Ag2S/Ag2WO4 composite microrods, with lengths of 0.2-1 um and diameters of 20-30 nm, were fabricated by a facile sonochemical route. The as -synthesized products were intensively investigated by a series of physicochemical characterizations, such as N-2 physical adsorption, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, diffuser reflectance spectroscopy, X-ray photoelectron spectroscopy, photoluminescence spectroscopy and photocurrent response measurements. Ultrasonic irradiation yields an obvious improvement in the photocatalyst texture, for example, an increase in crystallinity and surface area. Moreover, sonochemically fabricated Ag2S/Ag2WO4 microrods display strong visible light absorption and a high transient photocurrent response. The produced intimate Ag2S/Ag2WO4 interface between Ag2S and Ag2WO4 crystal phases largely promotes the separation of photogenerated holes and electrons. High photocatalytic activity and stability were obtained over Ag2S/Ag2WO4 composite microrods. The dye degradation rate constant of Ag2S/Ag2WO4 was 4.7 times and 29.8 times higher than that of bare Ag2WO4 and Ag2S, respectively. (C) 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.