Exploring the impact of iron doping on the photocatalytic efficiency of TiO2 coatings produced on Ti via PEO.

In this study, composite coatings of TiO 2 /Fe3+ were developed by incorporating Fe(NO 3) 3 into TiO 2 -based coatings, produced via plasma electrolytic oxidation (PEO) on unalloyed titanium. The ability of these coatings to photodegrade methylene blue (MB) under visible light was investigated. The morphology, chemical composition, and optical properties of the PEO coatings were characterized using various techniques, including X-ray diffraction, scanning electron microscopy, photoluminescence spectroscopy, and UV–Vis diffuse reflectance. All coatings exhibited a porous structure, with phase analysis revealing the formation of anatase and rutile phases during the coating process. The coatings were also found to be hydrophobic. Increasing the concentration of Fe(NO 3) 3 in the composite coatings from 0 to 0.1 g/L resulted in a decrease in the optical band gap energy from 3.05 eV to 2.95 eV. The PEO coating with 0.10 g/L of Fe(NO 3) 3 showed the highest photocatalytic activity (PA), achieving 70 %. This improvement in PA is likely due to the formation of a heterojunction, which effectively separates electron/hole pairs. [ABSTRACT FROM AUTHOR]