Zirconium oxide structure prepared by the sol-gel route: I, the role of the alcoholic solvent

Sol-gel-derived powder samples of zirconia (ZrO2) prepared via the dissolut ion of zirconium n-propoxide in methanol, ethanol, and 2-propanol have been characterized mainly using perturbed angular correlations spectroscopy, as a function of temperature. Results indicate that the nanostructures and su bsequent thermal evolution are alcohol dependent: the shorter the alcohol c hain, the more hydrolyzed the product. ZrO2 powder that has been obtained u sing ethanol as the solvent is the product that exhibits the better stabili zation of the metastable tetragonal phase (t-phase). It undergoes a clear a nd detailed t(1)-form --> t(2)-form --> monoclinic ZrO2 thermal transformat ion and shows the highest activation energy against the transformation to t he monoclinic phase.