Preparation and Characterization of CeO2 Superfine Powder

The CeO2 superfine powder was prepared by the co-precipitation method, using the industrial grade Ce2(CO3)3 and NH4HCO3 as starting material and precipitating reagent, respectively. The precipitated precursons and the calcinated products were characterized by the thermogravimetric analysis/thermoanalysis (TGA/DTA), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The results show that using NH4HCO3 as a precipitating reagent, the precipitate decomposed full as it was heated to 360 ℃. The CeO2 superfine powder formed by calcinating the precipitate belongs to a cubic CaF2-type stru cture and has the first mean particle diameter 140 nm and second mean particle diameter 630 nm. The CeO2 powder particles aggregate and grow with raising the calcination temperature.