Adsorption study of micropore structure of tin dioxide

The micropore structure of xerogels of tin dioxide prepared by precipitation is studied by the physical adsorption of N-2, O-2, and H-2 at -195.6 degrees C. The parameters of the microstructure as a whole depend on the adsorbate. The specific surface area of supermicropores measured by the oxygen adsorption exceeds that measured by nitrogen adsorption, and the extent of excess increases linearly with an increase in the supermicropore volume. The samples of tin dioxides have molecular-sieve properties, but they do not contain ultramicropores measurable by the adsorption of molecular hydrogen.