Antifungal capability of TiO2 coated film on moist wood

Photocatalytic oxidation by TiO2 has been shown to deactivate biological pollutants. Most previous studies evaluated TiO2ʹs antimicrobial performance using bacteria, with Escherichia coli most commonly applied as the test microbe. There have not been concentrated studies focusing on the photocatalytic disinfection of fungi which widely exist in buildings and cause health problems. In this study, the antifungal activity of TiO2 photocatalytic reaction against Aspergillus niger was investigated for moist wood boards during periods of several weeks. TiO2 coated film in the presence of UVA (365 nm) irradiation exhibited antifungal capability. No visible growth was observed on specimens during the photo-process. Re-growth appeared in subsequent dark, indicating that the photocatalytic reaction was not sufficient for total disinfection against mold fungi but did suppress fungi growth. The study sheds light on conditions and potential applications of photocatalytic deactivation of fungi.