Effect of TiO2 nanoparticles on the photocatalytic properties of PEO coatings on Mg alloy

Abstract

A comprehensive study of the properties of coatings formed on a magnesium alloy by plasma electrolytic oxidation (PEO) using the electrolytes with nanosized particles of anatase (titanium dioxide) has been carried out. Formed coatings reduce corrosion current density 2.5-fold and increase hardness by 25% compared to a coating without particles. Confocal micro-Raman spectroscopy revealed the presence of anatase and rutile phases in the composition of PEO coating due to the incorporation of TiO2 nanoparticles during plasma electrolytic treatment. The presence of titanium dioxide had a positive effect on the photocatalytic properties of coatings: the constant rate of the methyl orange and methyl blue decomposition is increased in 1.6 and 1.8-fold, respectively, compared to the coating formed in electrolyte without TiO2 particles.

Keywords

• Plasma electrolytic oxidation
• Nanoparticles
• Titanium dioxide
• Photocatalysis
• Protective coatings