Synthesis and characterization of Fe-doped ^TiO ₂ photocatalyst by the sol–gel method

Abstract

Thin layers of pure TiO 2 and TiO 2 doped by different amounts of Fe 2 O 3 have been prepared by the sol–gel method with tetraisopropyl orthotitanate and Fe(NO 3)3. Physico-chemical properties of catalysts were characterized by BET Adsorption, x-ray Diffraction (XRD), FE-SEM, as well as Raman and UV-Vis spectroscopy. The photocatalytic activity of the obtained materials was investigated in the reaction of complete oxidation of p-xylene in gas phase under the radiation of UV (λ=365 nm) and LED (λ=470 nm) lamps. It has been found that the particle size of all samples was distributed in the range 20–30 nm. The content of the rutile phase in Fe-doped TiO 2 samples varied in the range 6.8 to 41.8% depending on the Fe content. Iron oxide doped into TiO 2 enables the photon absorbing zone of TiO 2 to extend from UV towards visible waves as well as to reduce its band gap energy from 3.2 to 2.67 eV. Photocatalytic activities of the TiO 2 samples modified by Fe 3+ have been found to be higher than those of pure TiO 2 by about 2.5 times.

Thin film nano-photocatalyts with low band gap energy for gas phase degradation of p -xylene: TiO 2 doped Cr, UiO66-NH 2 and LaBO 3 (B = Fe, Mn, and Co)

“…This may be related to the fact that TiO 2 and UiO66-NH 2 catalysts absorb the near-visible light of the high-intensity UV lamp, which facilitates the carbon deposit on the catalyst surfaces that should lead to reduce in activity. Meanwhile, the four catalysts of second group absorbed the visible light of lowlight LEDs, resulting in lower carbon deposit and catalysts work stability, as already found in article [34]. Perovskites LaFeO 3 and Cr-TiO 2 thin film were the best photo-catalysts under combined UV + LED illumination with a yield reached up to 1.70 g p-xylene /g cat .…”

APPLICATION OF SELF–CLEANING TREATMENT ON COTTON AND PES/CO FABRIC USING TiO2 AND SiO2 COATING SYNTHESIZED BY SOL–GEL METHOD

“…Infrared spectroscopy revealed that no modification of the cotton could be detected after photo-discoloration processes with TiO 2 -SiO 2 , taking a wine stain as model compound. The mixed TiO 2 and SiO 2 colloids lead during the dip-coating and subsequent thermal treatment on cotton to an organized structure of highly dispersed TiO 2 particles always surrounded by amorphous silica [4,6,7,8]. Therefore, this study demonstrates that the photocatalytic activity of TiO 2 -SiO 2 coated and TiO 2 coated on 100% cotton and PES/Co fabrics can be successful by the self-cleaning of red wine stains and coffee stains.…”

Cr-Doped TiO<sub>2</sub> Thin Films Prepared by Means of a Magnetron Co-Sputtering Process: Photocatalytic Application

“…This evolution could be linked to the presence of acceptor states in the bandgap. Transition metals could also make significant changes on the electronic structure of a crystalline material and thus on the values of the gap energy [25] [26]. The decrease in the gap energy makes TiO 2 -Cr films wider range absorbers of UV-Visible light, constituting a major advantage in terms of photovoltaic applications.…”