Visible-light-driven boron/ferrum/cerium/titania photocatalyst
A boron/ferrum/cerium/titania photocatalyst with visible-light-induced performance was prepared by the conventional sol–gel method, in which tetrabutyl titanate (Ti(O-nC4H9)4) was used as the precursor and boric acid (H3BO3), ferric nitrate enneahydrate (Fe(NO3)3·9H2O), and cerium nitrate hexahydrate (Ce(NO3)3·6H2O) were the sources of boron, ferrum, and cerium, respectively. The microstructure and optical property of the photocatalyst were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), N2 adsorption–desorption isotherm, and UV–vis diffusive reflectance spectroscopy (DRS). It was found that the as-prepared photocatalyst composed of anatase and that the presence of impurities could retard phase transformation of TiO2 from anatase to rutile at elevated temperatures and could prohibit growth of polycrystalline, which favored forming photocatalyst with large surface area. Degradation of 2,4-dichlorophenol (DCP) under visible light illumination was used to evaluate the photocatalytic activity. Comparative investigations showed that photocatalytic performance of the boron/ferrum/cerium/titania photocatalyst was the highest among the all test samples. It was testified that boron doping led to the band gap narrow and the response to visible light, and that ferrum and cerium impurities, which presented in the forms of FeO/Fe2O3 and Ce2O3/CeO2, dispersed on the surface of TiO2, suppressed the electron and hole recombination, and resulted in the enhancement of catalytic performance. The results exhibited that the synergistic effects of boron, ferrum and cerium played an important role in the band gap narrow and the increase of photoactivity.
Journal: Journal of Photochemistry and Photobiology A: Chemistry - Volume 200, Issues 2–3, 15 December 2008, Pages 141–147