Journal of the American Ceramic Society, Vol.91, No.2, 603-606, 2008
Nanocrystalline scandia powders via oxalate precipitation: The effects of solvent and solution pH
Nanocrystalline Sc2O3 was synthesized via precipitation with scandium nitrate as the scandium source and oxalic acid as the precipitant, with investigations into the influences of solution pH and solvent type on powder properties. Three types of scandium precursors (normal oxalate, double oxalate, and oxyhydroxide) have been obtained from aqueous media by adjusting pH of the precipitant solution with ammonia water. All the precursors, however, yield severely aggregated Sc2O3 powders of low surface areas. Replacing water with pure ethanol as the solvent was shown to be able to yield Sc2O3 nanopowders of high specific surface area (35.7 m(2)/g) and good dispersion. The mechanisms of solution pH and solvent type on precursor properties were also discussed.