Photocatalytic sterilization of TiO₂ films coated on Al fiber

Photocatalytic TiO₂ films were coated on Al fiber by sol-gel dip-coating method, and then annealed. The crystal structure and morphology of the films were performed by XRD, TEM and SEM. Photocatalytic sterilization of the films was investigated in O₂ atmosphere through purifying the aqueous solution with facultative aerobe (Bacillus cereus), aerobe (Pseudomonas aeruginosa) and anaerobe (Staphylococcus aureus, Enterococcus faecalis and Escherichia coli). In the presence of O₂, it benefits to generate O₂{radical dot}^- and {radical dot}OH at the first stage of the photocatalytic reaction, while the excess O₂ restrains the anaerobe from reproducing and accelerates the reproducing for the aerobe at the second stage of reaction. As a result, it was found that the crystal of TiO₂ films is anatase phase and the films have excellent sterilization effect against facultative aerobe and anaerobe. Nevertheless, it only decreased the bioactivity against aerobe in a short time.