No abstract

The hybrid nanocomposite material of bacterial cellulose (BC) nanofibers and titaniumdioxide (TiO 2 ) nanoparticles with improved visible light sensitivity was developed by doping nitrogen (N) and fluorine (F) on TiO 2 nanoparticles embedded on BC nanofibers. To synthesize TiO 2 nanoparticles on BC produced by Acetobacter xylinum (TISTR 975), titanium tetraisopropoxide (TTIP) was used as a titanium source and was directly hydrolyzed on BC nanofibers. After providing heat via the reflux technique to BC/TiO 2 pellicle, the crystalline structure of TiO 2 was changed to an anatase form on a three dimensional network structure of BC confirmed by XRD. Nitrogen (N) and fluorine (F) were successfully doped into TiO 2 nanoparticles by using NH 4 F as the source of N and F (BC/N-F-co-doped TiO 2 ). The TEM results showed that the average particle size of BC/N-F-codoped TiO 2 was smaller than the BC matrix containing none of the co-doped TiO 2 (BC/TiO 2 ) and N-doped TiO 2 (BC/N-TiO 2 ). In addition, BC/ N-F-co-doped TiO 2 demonstrated the high efficiency of photocatalytic disinfection activity against both gram-negative and gram-positive bacteria under fluorescence light. Nevertheless, the photocatalytic antibacterial activity of N-F-co-doped TiO 2 also depended on the type of bacteria, and degree of N-F-co-doped TiO 2 .