Nanocatalyst from sol–sol doping of TiO2 with Vanadium and Cerium and its application for 3,4 Dichloroaniline degradation using visible light

• The TiO2–Vanadium photocatalysts have higher visible light response with low particle size and high surface area.
• Doping of TiO2 was done using sols of Vanadium and Cerium instead of salts of the elements.
• TiO2–V showed better photocatalytic activity over 3,4 DCA with effective charge transfer than Ti–Ce.
• The kinetic did not follow Langmuir Hinshelwood model but followed a two regime First order kinetic model.
• Intermediates determined using HPLC analysis showed a complete degradation with the formation of CO2 and water.

Sol of Cerium and sol of Vanadium were used for doping with TiO2 by hydrothermal calcination method. The prepared catalyst referred to Ti–V and Ti–Ce were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photo electron spectroscopy (XPS), BET surface area, diffuse reflectance spectra (DRS) and Fourier transform infrared spectroscopy (FTIR). The prepared catalyst based on the characterization studies indicated that the particles were nanosize and TiO2 was in anatase phase. The DRS analysis, showed that Ti–V showed more shift towards visible region than Ti–Ce which reflected in the better activity of degradation of 3,4 Dichloroaniline. The Ti–V photocatalysts showed higher photocatalytic activity under visible light irradiation. This is attributed to the synergetic effects of red shift in the absorption edge, higher surface area and the inhibition of charge carrier recombination process. The degradation process followed First order kinetic model with two regimes and the rate constants were found to increase after 45 min of irradiation. The major intermediates formed were determined using HPLC which showed the reduction of the aromatic compounds to carbon dioxide, water and salts. The 7 intermediates formed were qualitatively confirmed using GC/MS analysis.

Proposed degradation mechanism of 3,4 Dichloroaniline.Figure optionsDownload as PowerPoint slide