Photocatalytic activity of titania–silica mixed oxides prepared with co-hydrolyzation

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2009
Bayram, Bilal
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TiO2 in anatase form is the most widely studied material for photocatalytic reactions. Utilization of oxide support materials such as silica with suitable transparency within band gap range of TiO2 is promising technique to obtain efficient photocatalysts for many applications. In the present study, simultaneous co-hydrolyzation of tetraethyl orthosilacate (TEOS) and titanium tetrabutaoxide (TBOT) precursors were carried out in the presence of hydrochloric acid. The effects of washing with low vapor pressure solvent(n-octane), drying conditions, hydrothermal ageing and TiO2/SiO2 ratio on the catalyst structure and photocatalytic activity were studied. The samples were characterized by XRD, BET, DRIFTS techniques and the activity was measured for liquid phase room temperature oxy/demineralization of phenol under artificial solar irradiation. The reaction intermediates were followed by UV/vis spectrophotometer and HPLC. It was found that the hydrothermal treatment contributes better degree of crystalinity, higher surface area and thus photocatalytic activity compared to the samples which were synthesized with conventional drying at 100oC overnight. The formation of Ti-O-Si interface indicating the degree of dispersion was evidenced by DRIFTS technique for all hydrothermally tretated samples. The highest surface area and photocatlytic activity was observed with hydrothermally treated catalyst with TiO2/SiO2:0.34 composition.
Chemical engineering., Photochemistry.
http://etd.lib.metu.edu.tr/upload/2/12611056/index.pdf
https://hdl.handle.net/11511/18831
Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats
B. Bayram, “Photocatalytic activity of titania–silica mixed oxides prepared with co-hydrolyzation,” M.S. - Master of Science, Middle East Technical University, 2009.
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