Surface functionalization of cellulose fibers with titanium dioxide nanoparticles and their combined bactericidal activities

A well-adherent surface of titanium oxide nanoparticles was produced on cellulose fibers at low temperature from an aqueous titania sol that was obtained via hydrolysis and condensation reactions of titanium isopropoxide in water. SEM investigations of the formed titania films revealed a semi-spherical particle morphology with grain size about 10 nm in diameter. The coated substrates showed substantial bactericidal properties under UV radiation, ambient fluorescent white light and dark conditions. The possible mechanisms for the antibacterial activity are discussed. The stability of the titania coatings was investigated by comparing the UV transmission profiles of coated fibers before and after repeated washing.