CeO 2 nanocrystalline particulates with different sizes were prepared by precipitation method using ethanol as dispersive and protective reagent. XRD patterns show that the synthesized CeO 2 is cubic in structure with space group O 5 H F M3M when calcination temperature is within 250~800 ℃. TEM photographs reveal that CeO 2 particles are spherical in shape. The mean sizes of the particles increase with the increase of calcination temperatures. Thermogravimetric analysis indicates that we...