Facile fabrication of Fe-TiO(2) thin film and its photocatalytic activity

Fe(3+)-TiO(2) (Fe-TiO(2)) thin films were successfully prepared using a “sandwich” approach. TiO(2) NPs were doped with different Fe(3+) content (0.05%, 0.1%, 0.2% molar ratio), and the modified TiO(2) NPs were deposited on glass flat support by dip coating. Structural, morphological, optical, and photocatalytic properties of Fe-TiO(2) thin films were studied. XPS spectra confirm the presence of Ti, Fe, O, and defective –OH groups at the material surface. The Fe 2p spectrum demonstrates the existence of Fe(3+). SEM images indicate that the incorporation of Fe(3+) deforms in some degree the homogeneity of the TiO(2) system. Additionally, incorporation of Fe(3+) ions to the network creates an impurity band near the VB due to the oxygen vacancies, resulting in the reduction of the effective optical band gap. Photocatalytic activity of fabricated thin films in the elimination of sulfamethoxazole (SMT) follows pseudo first-order kinetics. The highest SMT removal yields were achieved using the sample with 0.05%Fe. Additionally, the use of greater thicknesses improves the removal performance. However, material detachment limits the maximum usable value around 6 µm. Finally, stability and reusability of catalysts were confirmed studying the photocatalytic activity over three cycles and evaluating that no Fe(3+) leaching occurred. GRAPHICAL ABSTRACT: [Image: see text]