Reactive Ceria Nanopowders via Carbonate Precipitation

Nanocrystalline CeO 2 powders have been successfully synthesized via a carbonate precipitation method, using ammonium carbonate (AC) as the precipitant and cerium nitrate hexahydrate as the cerium source. The AC/Ce 3+ molar ratio ( R ) affects significantly precursor properties, and spherical nanoparticles can be produced only in a narrow range of 2 < R ≤ 3. The precursor, having an approximate composition of Ce(OH)CO 3 ·2.5H 2 O, decomposes to CeO 2 at temperatures ≥300°C. The CeO 2 powder calcined at 700°C exhibits high reactivity and can be densified to >99% of theoretical at 1000°C.