Jg. Yu et al., Effect of surface structure on photocatalytic activity of TiO2 thin films prepared by sol-gel method, THIN SOL FI, 379(1-2), 2000, pp. 7-14
TiO2 thin films with different surface structures are prepared from alkoxid
e solutions containing polyethylene glycol (PEG) via the sol-gel method. Th
e effects of PEG addition to the precursor solution on the surface structur
es and photocatalytic activity of the resultant thin films are studied. The
larger the amount of PEG added to the precursor solution, the larger the s
ize and number of pores produced in the resultant films when PEG added to t
he gel films decomposed completely during heat-treatment. The adsorbed hydr
oxyl content of such porous thin films is found to increase with increasing
amount of PEG. However, the transmittance of the films decreases due to th
e scattering of light by pores of larger size and bigger number in the film
s. Photocatalytic degradation experiments show that methyl orange is effici
ently decolorized in the presence of the TiO2 thin films by exposing its aq
ueous solution to ultraviolet light and the suitable surface structures rem
arkably enhance the photocatalytic activity of TiO2 films. (C) 2000 Elsevie
r Science B.V. All rights reserved.