1D TiO 2 Nanostructures Prepared from Seeds Presenting Tailored TiO 2 Crystalline Phases and Their Photocatalytic Activity for Escherichia coli in Water

CABRERA, JULIETA; ACOSTA, DWIGHT; LÓPEZ, ALCIDES; CANDAL, ROBERTO J.; MARCHI, CLAUDIA; GARCÍA, PILAR; RÍOS, DANTE; RODRIGUEZ, JUAN M.

INTERNATIONAL JOURNAL OF PHOTOENERGY

HINDAWI PUBLISHING CORPORATION

Lugar: New York; Año: 2018 vol. 2018 p. 1 - 6

1110-662X

TiO2 nanotubes were synthesized by alkaline hydrothermal treatment of TiO2 nanoparticles withcontrolled proportion of anatase and rutile. Tailoring of TiO2 phases was achieved by adjustingpH and type of acid used in the hydrolysis of titanium isopropoxide (first step in the sol-gelsynthesis). Anatase proportion in the precursor nanoparticles was in the 3-100% range. Tubelikenanostructures were obtained with anatase percentage of 18 or higher while flake-likeshapes were obtained when rutile was dominant in the seed. After annealing at 400°C for 2 h, afraction of nanotubes was conserved in all the samples but, depending on the anatase/rutile ratioin the starting material, spherical and rod shape structures were also observed. Thephotocatalytic activity of 1D nanostructures were evaluated for E. coli bacteria in water in twoconditions under magnetic stirring, in dark and UV-A/B irradiation. Results shown that inaddition to bactericidal activity of TiO2 under UV-A illumination, under dark conditions, thedecreasing of bacteria viability is adscribed to mechanical stress due to stirring.