Hydrothermal preparation of Ag-TiO2-reduced graphene oxide ternary microspheres structure composite for enhancing photocatalytic activity

Abstract

Photocatalysis technology is considered to be the most industrially feasible way to degrade industrial pollutants due to its low energy consumption and high efficiency. Graphene is considered to be the most potential carrier. Therefore, introducing it into TiO2 has great significance. In this study, We report Ag nanoparticles - modified TiO2 microspheres deposited on reduced graphene oxide (rGO) sheets material was prepared by two-step hydrothermal method. X-ray diffraction (XRD) analysis confirmed that the TiO2 microspheres are typical anatase phases and has the presence of Ag nanoparticles. The characterization of Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) indicated that the graphene oxide was well reduced to rGO, which binds well to Ag-TiO2 microspheres. The prepared 2% Ag-TiO2-rGO microspheres composite showed the best degradation efficiency when degrading Rhodamine B, which caused RhB to degrade 96% in 100 min. At the same time, The modification of Ag nanoparticles on TiO2 microspheres facilitates the separation of photogenerated electron-hole pairs of TiO2, and electrons are further transferred to rGO to participate in photocatalytic reactions. In addition, the composite of rGO also increases the specific surface area of the sample, which is more favorable for the adsorption of dye molecules, so that 2% Ag-TiO2-rGO microspheres composite showed the highest efficiency for photodegradation of RhB.