Abstract: N-F-codoped TiO₂ semiconductor Sol (N-F-TiO₂) was synthesized by Sol-Gel method, and N-F-TiO₂ film was prepared on soda-lime glass using silk-screen printing. X-ray diffraction (XRD) of N-F-TiO₂ exhibits significant diffraction peaks representing the characteristic of anatase phase and contain trace amount of brookite. X-ray photoelectron spectroscope (XPS) test indicates that N element exists with N-Ti-O bonding in the crystals, while F element exists as a dopant in the lattice of TiO₂ or adsorbs on the surface of N-F-TiO₂. Diffuse reflectance spectra (DRS) of N-F-TiO₂ shows increased absorption in the range of 300-500 nm compared with that of undoped TiO₂ film. Antibacterial abilities of N-F-TiO₂ films under 60min UV and visible light irradiation are identified using E.coli. The prepared N-F-TiO₂ films exhibit excellent antibacterial abilities as observed both in bacterial surviving test and cell membrane damaging test. After the irradiation of UV-A, the relative survival percentage of E.coli decreases to 0 and the maximum content of malonaldehyde (MDA) is 1.4 nmol/mg (cell dry weight). Under the visible light irradiation, relative survival percentage of E.coli decreases to 10% and the maximum content of malonaldehyde is 0.9 nmol/mg (cell dry weight).

Key words: nitrogen doping, fluorine doping, TiO₂ film, photocatalysis, sterilization