A. Petin, V. Gun'ko, A. Turov, V. Turov and R. Leboda
Clusterization of water at a surface of nanosilica A-380
Thermodynamic and structural characteristics of water (0.07-1 g per 1 g of silica) bound to nanosilica A-380 (SBET = 378 m2/g, primary particle diameter 7.2 nm) alone or on co-adsorption with chloroform alone or in the mixture with DMSO or acetonitrile were determined using 1H NMR spectroscopy with layer-by-layer freezing-out of water at 200-273 K and NMR-cryoporometry.
V. Gun'ko, V. Bogatyrev, R. Leboda, J. Skubiszewska-Zięba, L. Petrus, Y. Nychiporuk, O. Oranska, O. Dudarko, V. Osovskii and Y. Ptushinskii
Titania deposits on nanosilicas
Titania (content CTiO2 = 2.7-20.0 wt%) was synthesized on different fumed silica substrates (A-50, A-100, A-380) using Ti[OCH(CH3)2]4 as a precursor interacting with silica/adsorbed water in 2-propanol or CCl4 medium, dried and then heated at 1073 K for 1 h. Initial and pretreated nanosilicas and titania/silicas were studied using XRD, adsorption, FTIR, TEM, AFM, and TPD-MS methods. The morphology of grafted titania (anatase/rutile/amorphous phase composition, particle size distribution, aggregation, textural porosity) depends on the types of a nanosilica matrix and a solvent, suspension treatments and reaction conditions.