Synthesis of CeO2 Nanocrystalline Powder by Precipitation Method

Ceria (CeO2) is an important rare earth oxide and has been widely investigated in the automotive exhaust puri cation, oxygen storage and release catalysis, and solid oxide fuel cell applications. In recent years, due to the excellent physical and chemical properties of nanosized particles, which are signi cantly different from those of bulk particles, there is considerable interest in enhancing catalytic activity, sinterability, and other properties by decreasing the grain size into a nanometer range. In the present study, a simple precipitation procedure for the synthesizing of CeO2 nanocrystalline powder (~13 nm) is presented. The structural evolutions and morphological characteristics of the nanopowder were investigated using X-ray diffractometry (XRD), scanning electron microscopy (SEM), thermo-gravimetry (TG), and Fourier transform infrared spectroscopy (FTIR). XRD results showed that face centered cubic CeO2 particles with crystallite size in nanometer scale were formed. By increasing the calcination temperature from 100 to 300°C, the crystallite size decreases from 20 to 13.9 nm. By increasing the temperature more than 300°C, crystallite size of ceria increases. SEM studies showed the morphology of the prepared powder is sphere-like with a narrow size distribution.