Adsorption study of micropore structure of tin dioxide

The micropore structure of xerogels of tin dioxide prepared by precipitatio n is studied by the physical adsorption of N-2, O-2, and H-2 at -195.6 degr ees C. The parameters of the microstructure as a whole depend on the adsorb ate. The specific surface area of supermicropores measured by the oxygen ad sorption exceeds that measured by nitrogen adsorption, and the extent of ex cess increases linearly with an increase in the supermicropore volume. The samples of tin dioxides have molecular-sieve properties, but they do not co ntain ultramicropores measurable by the adsorption of molecular hydrogen.