Antimony-Doped Tin Oxide Aerogel Based on Epoxide Additional Method

Antimony-doped tin oxide (ATO) aerogels were prepared from inorganic salts via epoxide additional method, CO2 supercritical fluid drying and thermal treatment. ATO samples were dark blue monoliths with average density of about 600 mg.cm(-3) and Sb concentrations of 5%-20%(x). Electron microscopy showed that the skeleton of the ATO aerogels consisted of particles of size of dozens of nanometers, which further consisted of primary particles of size about several nanometers. X-ray diffraction spectra showed that the main crystal structure within the ATO aerogels was tetragonal tin dioxide, while Sb doping only resulted in minor lattice distortion. X-ray photoelectron spectroscopy indicated that the valence state of tin was +4, while antimony was mixed with +3 and +5 valences. Four-point probe resistivity analysis exhibited that the electrical resistivity of the ATO aerogels changed from 2.7 to 40 Omega.cm, among which the aerogel with 12% Sb had the lowest resistivity.