Fabrication and photocatalytic activity of MAO–TiO2 films formed on titanium doped with cations

The microarc oxidation (MAO) TiO2 films were fabricated in phosphate based electrolyte under different voltages on titanium to study the optimum voltage for photocatalysis, and then the doping process was carried out under the optimum condition above. The surface morphology and composition of MAO films were examined by scanning electron microscopy and X-ray diffraction. The photocatalytic activities of MAO films with and without cation dopant were evaluated by photocatalytic decolourisation of methylene blue in aqueous solution as a model pollutant under simulated sunlight irradiation. The results showed that the photocatalytic activity of MAO–TiO2 films first increased and then decreased with increasing the voltage, and the cation dopant enhanced the photocatalytic activity of MAO–TiO2 films. Moreover, the transition metal cation Cu2+ was more suitable for dope than the rare earth metal cation Ce4+ to some extent.