Plasma electrolytic titanium oxide applied for pathogenic bacteria inactivation

ABSTRACTPhotocatalysis over TiO2 substrates is widely used in effluent treatment specially for organic compounds and for inactivation of pathogenic microorganisms. In the present work, TiO2 coatings were synthesized by plasma electrolytic oxidation (PEO) and its pathogenic bacteria inhibitory photoactivity was investigated. The photocatalytic activity of TiO2 coatings was investigated for the inactivation of Staphylococcus aureus and Salmonella bongori and the results were correlated with pore diameter and crystallite size. It was observed that both morphology and microstructure have an important role in the antibacterial photoactivity. The results show the larger the crystallite size and pore diameter the greater the photoactivity of the material. Porous materials that have a smaller pore diameter than the microorganism to be inactivated have low photoactivity. On the other hand, films that have pores with a diameter of the order or larger than the size of the microorganism to be inactivated present grea...