Characterization and activity of the Ce and N co-doped TiO2 prepared through hydrothermal method

The Ce/N co-doped TiO2 was prepared through hydrothermal method by using cerium nitrate and tetrabutyl orthotitanate (TBOT). Samples were characterized by different techniques such as. X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), fourier transformation infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV-visible diffuse reflectance spectroscopy (UV-vis. DRS) and photoluminescence spectroscopy (PLS). The XRD and Raman spectra showed only anatase phase of TiO2 for the pure, single doped and co-doped samples. The XPS of Ce showed the presence of both Ce3+ and Ce4+ oxidation states. The PLS of the samples showed first decrease in the recombination centers when Ce was introduced in co-doped TiO2 with the maximum decrease for 0.05 Ce/N co-doped TiO2 and then started increasing with the increase of Ce in the samples. We found a direct relationship between the amount of recombination centers and photoactivity of the samples, which was evaluated by the decolorization of 25 mg/L solution of Acid Orange 7 (AO-7). The activities of co-doped samples were highly increased by the incorporation of Ce with the maximum degradation exhibited by 0.05 Ce/N-TiO2 sample. (C) 2013 Elsevier B.V. All rights reserved.