Abstract
Structural analysis in the range of characteristic sizes from 1 nm to ~1.5 µm was performed for SiO
2
–TiO
2
aerogels prepared in supercritical CO
2
, isopropanol, hexafluoroisopropanol, or methyl-
tert
-butyl ether using small-angle X-ray scattering and neutron scattering complementary methods. A two-level model that accounts for scattering by individual inhomogeneities and their aggregates, which have fractal properties, satisfactorily describes the aerogel structures over the entire range of scales. It is shown for the first time that the titania concentration is the key factor in the small-angle neutron and X-ray scattering by SiO
2
–TiO
2
aerogels. The phase composition of an aerogel does not significantly affect the aerogel structure in the range of scales from 1 nm to ~1.5 µm, as probed by small-angle X-ray and neutron scattering.