Preparation of ultrafine CeO2 powders by microwave-induced combustion and precipitation

A novel procedure for synthesizing submicron crystalline single-phase ceramic powder was investigated. Ultrafine CeO2 powder was successfully prepared by combustion of mixture of cerium nitrate (oxidizer) and urea (fuel) in microwave oven for 15 min. The ultrafine powder was studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), differential thermal analysis and thermogravimetric analysis (DTA/TG); surface area measurement was also made. The results indicated that the CeO2 powders synthesized by microwave-induced combustion had particle sizes ranging from 20 to 50 nm, and specific surface areas of approximately 43 m2/g. In comparison, CeO2 powder prepared by precipitation revealed particles of sizes distributed from 30 to 50 nm, with a specific surface area of about 48 m2/g.