Study on photocatalytic performance of TiO2 and Fe3+/TiO2 coatings

The TiO2 coatings were fabricated in phosphate-based electrolyte on pure titanium by micro-arc oxidation (MAO); then, they were impregnated with Fe3+-containing electrolyte to produce the Fe3+/TiO2 composite coatings. The physical and chemical properties of two coatings were investigated by SEM, XRD, AFM, XPS and EDS. A UV-vis spectrophotometer was also used to study photocatalytic properties of the coatings. It is indicated that the coating formed in phosphate-based electrolyte were composed of anatase and rutile phase with varying fraction depending on the applied frequency. XPS results revealed that Ti 2p spin-orbit components of Fe3+/TiO2 composite coatings are shifted towards higher binding energy, with respect to TiO2 coatings, suggesting that some of the Fe3+ ions are incorporated into TiO2 lattice. The Fe3+/TiO2 composite coatings showed an obvious enhanced photocatalytic activity than that of the TiO2 coating under irradiation.