Defects in nanocrystalline ceria xerogel

Nanocrystalline ceria was produced via sol-gel from Ce alkoxides with and without the addition of water and a chelating agent (acetylacetone). Microstructure analysis of the resulting powder was conducted on laboratory and synchrotron radiation data using the Whole Powder Pattern Modelling algorithm. It is shown that the synthesis with water leads to smaller and more defective particles and that aggregation of the crystalline domains occurs at temperatures as low as 80°C. The route to the formation of the ceria nanograins is explained in terms of balance of competing condensation reactions.