Characterization of Titania/Silica Gel by Means of Low-Pressure Nitrogen Adsorption.
Adsorbents synthesized by grafting of titania onto mesoporous silica gel surfaces at different temperatures were studied by means of nitrogen adsorption-desorption and water desorption. The pore size distribution f(R(p)) of titania/silica gel depends on the titania concentration (C(TiO(2))) and the temperature of titania synthesis. Nonuniformity of TiO(2) phase is maximal at a low C(TiO(2)) value (3.2 wt.% anatase deposited at 473 K), and two peaks of the fractal dimension distribution f(D) are observed at such a concentration of titania, but at larger C(TiO(2)) values, only one f(D) peak is seen. More ordered filling of pores and adsorption sites by nitrogen, reflecting in the shape of adsorption energy distributions f(E) at different pressures of adsorbate, is observed for adsorbent with titania (rutile+anatase) grafted on silica gel at a higher temperature (673 K). Copyright 2000 Academic Press.
Gun'ko
VM
Institute of Surface Chemistry, 31 Prospect Nauki, Kiev, 03680, Ukraine
Villiéras
F
Leboda
R
Marciniak
M
Charmas
B
Skubiszewska-Zi&ecedil;ba
J