Synthesis and photocatalytic activity of nano V-doped TiO₂ particles in MCM-41 under UV–visible irradiation

The vanadium (V)-doped titania (Ti_0.95V_0.05O₂) was impregnated in the host matrix of the pre-synthesized siliceous mesoporous material MCM-41 in a single pot synthesis step, by the wet impregnation route. The samples were characterized by x-ray diffraction, transmission electron microscopy (TEM), N₂ adsorption, diffuse reflectance ultraviolet–visible spectroscopy (DRUVS). As compared to Ti_0.95V_0.05O₂, the DRUV spectra of the impregnated catalysts showed a blue shift; still the absorption lies in the visible region. Presence of nano-sized (∼2–12 nm) V-doped titania particles in V-TiO₂/MCM-41 was revealed by TEM and the particle size was found to increase with the loading of the V-doped titania in the host matrix. All impregnated samples were found to be more active than either the bulk V-doped titania or titania for photocatalytic oxidation of ethylene in air at ambient conditions under both UV and visible irradiation.