Photocatalytic Function of FeTiO₃ in Composite TiO₂-FeTiO₃ Coatings Prepared by Plasma Spray

The compositions and photocatalytic activity of plasma sprayed TiO₂, TiO₂-30%FeTiO₃, TiO₂-50%FeTiO₃ and FeTiO₃ coatings were investigated. The influence of FeTiO₃ compound on the photocatalytic activity of TiO₂ coating was clarified. The TiO₂-30%FeTiO₃ coating sprayed under the arc current of 400 A had good photocatalytic activity because the coating did not contain the unfavorable Fe₂TiO₅ phase. The relative deposition speed of TiO₂-30%FeTiO₃ powder under the arc current of 400 A was approximate to 4 µm/pass. Although pure FeTiO₃ compound nearly did not show photocatalytic performance, the existence of FeTiO₃ could improve the photocatalytic activity of anatase TiO₂ if FeTiO₃ contacts coherently with it, which was explained using two-steps electron transfer model.