Preparation and Characterization of Ordered TiO2 Photocatalysts: Films and Mesoporous Structures

Authors : Orçun ERGÜN, Osman KARSLIOĞLU, Ayşen YILMAZ, Deniz ÜNER

Pages : 501-508

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Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Two different ordered TiO2 structures were prepared as sol-gel films coated on glass and as mesoporous structures in order to study the effect, in 2-D or in 3-D, of bulk size on photocatalytic activity. Multilayer TiO2 films were coated on glass by the sol-gel dip coating method. The UV-VIS characteristics of the films, with respect to the number of coating layers, were monitored. UV-VIS measurements implied an ordered TiO2 structure grown on ITO glass. The second approach involved loading TiO2 in mesoporous SBA-15 powder. Ti-SBA-15 with Ti/Si insert ignore into journalissuearticles values(mole/mole); ratios between 0.05 and 0.30 were prepared and characterized by XRD and BET. Low-angle XRD results of Ti-SBA-15 samples demonstrated long-range order, and the mesoporous structure of SBA-15 was preserved under all titanium loadings. Wide-angle XRD results of Ti-SBA-15 samples demonstrated no crystallinity for TiO2 at low Ti loadings insert ignore into journalissuearticles values(0.05 and 0.10);, and the onset of crystal formation at the 0.15 loading. The rutile phase was observed to be the dominant phase for lower loadings insert ignore into journalissuearticles values(0.20);, whereas the anatase phase was dominant at higher loadings insert ignore into journalissuearticles values(0.25 and 0.30);. BET surface areas decreased slightly with the addition of TiO2 in SBA-15
Keywords : Turk J Chem, 31, 2007, 501 508 Turk J Chem, vol 31, iss 5