| As an ideal photocatalytic material, TiO2is very promising on energy saving andenvironmental protection due to its particular electronic band structure, low cost, non-toxicity,stable physical and chemical properties and high photocatalytic activity. However, both the lowutilization of solar light and poor quantum efficiency limit its wide application in industrialproduction and daily life. In this paper, we try to improve relative properties by dopingtransition metals into pure TiO2. The sol-gel method was used to fabricate the pure andmetal-doped anatase TiO2nano-powders with different concentrations. X-ray Diffraction（XRD）,Transmission Electron Microscopy（TEM）, X-ray Photoelectron Spectroscopy（XPS）,Photoluminescence Spectra （PL Spectra） and UV-vis diffuse reflectance spectra were used tocharacterize the obtained powders respectively. The photocatalytic activity of samples werechecked by decolorizing the methylene blue solution under visible light irradiation. We alsoused the first-principles calculation to conduct the relative theoretical analysis. The resultsappeared as follows. Doping transition metals Fe,Mo or V with the proper concentration intothe TiO2contribute to enhance the visible light absorption and photocatalytic activity. Fe-dopedTiO2with the concentration in the range of0.5%-1.0%exhibited the best photocatalyticproperty. For V-doped TiO2, the optimal doping concentration was about0.5%.1.0%Mo-TiO2could decompose about61%of the methylene blue molecular after visible light irradiation for3hours. Compared with Fe mono-doping,（Fe+Mo） co-doping could further enhance the visiblelight absorption and improve the photocatalytic property of TiO2due to charge incompletelycompensation. Doping small amount of Mo into Fe-doped TiO2is likely to be a way to improvethe photocatalytic property of Fe-doped TiO2without losing its photocatalytic specificity.However, charge completely compensated （Fe+V） co-doping would not promote thephotocatalytic activity of TiO2. |
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