The effect of nitrogen impurity on the antibacterial activity of TiO۲ under visible light media

Nitrogen-doped titanium oxide (TiON) nanoparticle photocatalysts were synthesized by a sol−gel process, for disinfection using E. coli as target bacteria. The crystalline structure, particle size and specific surface area of the resultant N–TiO۲ nanoparticles were investigated by x-ray powder diffraction and the Brunauer–Emmett–Teller method. The results showed that a mixture of anatase and rutile phases was formed after annealing the powder at ۴۵۰° C for ۴ h. UV–vis spectral characterization showed that the absorption region of the as-prepared N–TiO۲ was extended to the visible light region. Disinfection experiments on Escherichia coli indicate during the photocatalytic test, in comparison to the standard commercial photocatalyst Evonik-Degussa P۲۵ and home-made bare TiO۲ nanoparticles, the N–TiO۲ particles exhibited enhanced photocatalytic performance. The enhanced photocatalytic activity is related to stronger visible light absorption of the N-doped TiO۲.

Keywords:

nitrogen impurity , antibacterial activity , photocatalysts