Preparation and characterization of Ag-doped TiO2 nanomaterials and their photocatalytic reduction of Cr(VI) under visible light

Ag-doped TiO2 nanomaterials (Ag-TiO2) were prepared by a sol-gel method. The structures of Ag-TiO2 nanomaterials were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (DRS), X-ray photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetry and differential thermal analysis (TG-DTA), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), scanning electron microscopy (SEM) and nitrogen adsorption-desorption isotherms. The photocatalytic activities were checked through the photocatalytic reduction of Cr(VI) as a model compound under visible light irradiation. The results showed that the Ag doping and the calcination temperature played an important role on the microstructure and photocatalytic activity of the samples. Ag-doped TiO2 samples calcinated at 400 degrees C exhibits higher photocatalytic activity than that of the other samples under visible light irradiation. (C) 2014 Elsevier B.V. All rights reserved.