Preparation and Physical Properties of V2 O5 Aerogels

ABSTRACTMonolithic aerogels and aerogel coatings of hydrated V2O5 containing 0 to 10 mol% GeO2 were prepared from metal alkoxides by hydrolysis and autoclave drying. The bulk aerogels of high porosity, more than 90 %, were obtained. On the other hand, the porosity of the aerogel coatings, about 50 nm in thickness, was about 50 %. The aerogels consisted of micro fibrils, less than 20 nm in diameter. Diffraction peaks of crystalline vanadium oxides were not observed for the as-dried aerogels. Dynamic microhardness of the bulk aerogels was very low, but increased with addition of GeO2· Dc electrical conductivity of the bulk aerogels was lower than that of the bulk xerogels by one order of magnitude, and was isotropie. The aerogels were surface fractal with Ds ≅ 2.7.