Photocatalytic and antibacterial activity of Fe-doped TiO2 nanoparticles prepared by nonhydrolytic sol-gel method

In the present work we report synthesis of pure and iron doped TiO2 by nonhydrolytic sol-gel method using titanium tetrachloride, benzyl alcohol and iron(III) nitrate. The structure of the resulting particles was characterized by XRD, IR and UV-Vis spectroscopy. The average particles size of Fe-doped TiO2 was 12-15 nm. The photocatalytic activity of the as-prepared TiO2 powders was tested by photodegradation of the organic dye Reactive Black 5 under UV and visible irradiation in an aqueous suspension. Antibacterial action of pure and Fe-modified titanium dioxide samples was tested using Escherichia coli ATCC 25922. The bacterial growth was examined in the presence of a synthesized preparations - in dark and with UV light. The photodisinfection activity was assessed by plotting of survival curves and calculation of removal efficiency. In order to estimate the post-irradiation effect, the behavior of the bacterial suspension in presence of each photocatalyst after 24 h dark period was tested. The optimal iron content was found to be 0.5 mol% for the photocatalytic decomposition of Reactive Black 5 dye under ultra violet (UV) and visible (Vis) irradiation, and also for antibacterial activity in the presence of UV light. At higher iron contents (1-2 mol%) the photocatalytic performance under both UV and Vis irradiation was worse relative to the undoped TiO2.