Enhanced visible light photocatalytic activity of Ag2S-graphene/TiO2 nanocomposites made by sonochemical synthesis

Ag2S-graphene/TiO2 composites were synthesized by a facile sonochemical method. The products were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, and UV-Vis diffuse reflectance spectrophotometry. During the synthesis reaction, the reduction of graphene oxide and loading of Ag2S and TiO2 particles were achieved. The Ag2S-graphene/TiO2 composites possessed a large adsorption capacity for dyes, an extended light absorption range, and efficient charge separation properties. Hence, in the photodegradation of rhodamine B, a significant enhancement in the reaction rate was observed with the Ag2S-graphene/TiO2 composites as compared to pure TiO2. The generation of reactive oxygen species was detected by the oxidation of 1,5-diphenyl carbazide to 1,5-diphenyl carbazone. The high activity was attributed to the synergetic effects of high charge mobility and the red shift in the absorption edge of the Ag2S-graphene/TiO2 composites.

Graphical AbstractThis paper presents the research of synthesized Ag2S-graphene/TiO2 by the sonochemical method. The generation of reactive oxygen species was detected through the oxidation reaction from 1,5-diphenyl carbazide to 1,5-diphenyl carbazone.Figure optionsDownload as PowerPoint slide