Fe-TiO2 particles were synthesized by sol-gel process from hydrolysis of titanium tetra-isopropoxide with nitric acid and
ferric nitrate aqueous solutions (relative Fe:Ti molar ratio ranging from 1 to 6 at %) followed by hydrothermal treatment.
Thin films were deposited onto conducting glass electrodes from a suspension with polyethylene glycol and heating at
450 °C for 30 min, which resulted in 1.5 μm thick transparent porous films. Crystalline samples, 93 % anatase and 7 %
brookite, were obtained. Increasing the iron amount, the crystallite size estimated from XRD patterns ranged from 18 to
11 nm and the color varied from slightly yellow to brown. The optical properties have also changed; the absorption edge
shifted towards longer wavelengths, with band gap energy decreasing from 3.0 to 2.7 eV. The films exhibited
photocatalytic activity for phenol degradation that indicates promising applications in solar energy conversion.
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