Nanosized CeO2 powders obtained by flux method

Cerium(IV) oxide (CeO2) powders were prepared by the flux method, adding cerium ammonium nitrate ((NH4)2Ce(NO3)6) to an eutectic mixture of molten salts, followed by washing and drying. To evaluate the effect of the molten salts on the powders, three different fluxes were used: KOH/NaOH, NaNO3/KNO3, and LiCl/KCl eutectic mixtures. The temperature and the stoichiometry of each reaction were determined by thermogravimetric analysis. Specific surface area analysis (BET), transmission electron microscopy (TEM), and X-ray techniques were used to study the morphology and particle size distribution of the solid products. Results showed the presence, in the reaction products, of homogeneously sized and shaped particles of a single nanosized CeO2 phase. The powder obtained with chlorides out of molten salts had the finer particle size distribution, with a very narrow dimensional range of 20–10 nm.