Template-based approach in the preparation of nanoporous silicas and titania-silicas
Анотація
Mesoporous silicas and titania-silicas were synthesized with use as a template quaternary ammonium salts and their hydroxides. Fumed silica, tetraethyl orthosilicate and titanium(IV) tetraisopropoxide were applied as presursors. Syntheses were carried out in presence HCl and NH4OH. Mesoporous titania-silicas with TiO2 contents from 1 up to 70 mol. % were prepared. Obtained samples have been characterized by the powder X-ray diffraction data and nitrogen adsorption at 77 K. Specific surface area, total pore volume, pore volume and area distribution were determined from nitrogen adsorption isotherm for synthesized titania-silicas. It was demonstrated that the ordered structures of MCM-41 type and bimodal porous materials with maximum pore diameter of 3 and 30 nm may be prepared depending of a synthesis conditions and a precursor nature.
Посилання
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