Photocatalytic activity of TiO₂ film containing Fe₂O₃ via plasma electrolytic oxidation

This study investigated the photocatalytic activity of an Fe containing TiO 2 film produced in the FePO 4 electrolyte via the plasma electrolytic oxidation (PEO) method. For this purpose, the PEO process was carried out on titanium substrate under ac condition in two different alkaline electrolytes containing K 3 PO 4 and FePO 4 respectively. The structure, chemical composition and constituent phases of the PEO treated samples were analysed via SEM, X-ray photoelectron spectroscopy and X-ray diffraction. The optical properties of the samples were also examined by an ultraviolet–visible spectrophotometer. In terms of the photocatalytic activity judging from the decomposition of methylene blue under visible light illumination, the sample formed in the FePO 4 electrolyte was better than that in the K 3 PO 4 electrolyte due to the incorporation of an Fe compound that has a narrow band gap.