Antibacterial device using UVA-LED and TiO2 films for air-conditioner evaporator

Recently, photocatalysis with TiO2 was very restricted because of the lack of an appropriate UV source. In this work, in order to increase antibacterial properties of UVA-LED, photoreactive TiO2 film was coated on aluminum substrates by rf-magnetron sputtering. The number of Escherichia coli which remained after irradiation under each time was counted. The photocatalytic TiO2 films on aluminum after irradiation at 365 nm have the comparable antibacterial ability to the uncoated sample irradiated at 280 nm. A sterilization system integrating TiO2 film with UVA-LED has the potential for air purification in automobile and would find wide use in the field of antibacterial.