Influence of titanium dioxide modification on the antibacterial properties

Abstract

Antibacterial properties of 15 titania photocatalysts, mono-and dual-modifi ed with nitrogen and carbon were examined. Amorphous TiO 2 , supplied by Azoty Group Chemical Factory Police S.A., was used as titania source (Ar-TiO 2 , C-TiO 2 , N-TiO 2 and N,C-TiO 2 calcined at 300 o C, 400 o C, 500 o C, 600 o C, 700 o C). The disinfection ability was examined against Escherichia coli K12 under irradiation with UV and artifi cial sunlight and in dark conditions. It has been found the development of new photocatalysts with enhanced interaction ability with microorganisms might be a useful strategy to improve disinfection method conducted under artifi cial sunlight irradiation. The effi ciency of disinfection process conducted under artifi cial sunlight irradiation with carbon (C-TiO 2 ) and carbon/nitrogen (N,C-TiO 2 ) photocatalysts was similar as obtained under UV irradiation. Furthermore, during dark incubation, any toxicity of the photocatalyst was noted.

Carbon/Graphene-Modified Titania with Enhanced Photocatalytic Activity under UV and Vis Irradiation

“…On the other hand, the activity of P25 was negligible both under vis and in the dark conditions, due to its wide band-gap and "dark" inertness. Some reports proposed that vis-responsive bactericidal activity of carbon-modified (mainly doped) titania [13,[73][74][75][76][77] was cased by the presence of carbon and the direct interaction (e.g., redox reaction) between photocatalyst and bacteria. Interestingly, Wang et al proposed that the electron transfer between C-doped titania nanotubes and bacteria induced the intracellular ROS formation and cell death, evaluated by charging of sample [78].…”

“…Various sources of carbon have been proposed for titania modification, such as polyvinyl alcohol [10], n-hexane [11], alcohols (methyl, ethyl, isopropyl, n-butyl, 2-butyl and tert-butyl alcohols) [12], benzene [13], ethylene glycol and pentaerythritol [14] and glucose [15]. Interesting approach was proposed for carbon-doped titania nanostructures (micro-and nanospheres and nanotubes), synthesized via a single source vapor deposition in an inert atmosphere (Ar), where titanium butoxide (common organic precursor of titania) was used also as a carbon source [16].…”