Ceria nanopowders with a crystallite size of 5–20 nm have been prepared by the sol–gel method using cerium (III) nitrate, acetate or acetylacetonate as cerium source. Dimethyloctylamine, monoethanolamine, or tetraethylammonium hydroxide were used as low molecular weight stabilizers. In all cases ceria obtained have a mesoporous structure with pore diameter 3–5 nm. It is shown how the initial salt and stabilizer significantly affect the physical–chemical properties of the obtained ceria powders. Also the temperature of CO full conversion was demonstrated not to be dependent on particle size, surface area, or pore size.

The purpose of this study was to develop wet-chemistry approaches for the synthesis of ultradispersed and mesoporous metal oxide powders and powdery composites intended for usage in the production of ceramic materials with desired properties. The focus is on the development of template synthesis of mesoporous metal silicates as well as obtaining nano- and subnanopowders by a modified sol-gel technique and template methods. Families of mesoporous (2 to 300 nm) metal silicates and nano-oxides and subnanopowders (4 to 300 nm) were synthesized by the template method and modified sol-gel technique, respectively. Texture and morphology of the obtained objects have been studied by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller analysis, and N₂ adsorption-desorption. It was found that morphological parameters of the metal oxide obtained by the modified sol-gel technique depend nonlinearly on the initial molar ratio value of the sol stabilizer and metal in the reaction medium as well as the nature of the stabilizer. It has been shown that the nature of structure-directing components determines the morphology of the silicate obtained by the template method: dispersion and shape of its particles. The developed laboratory technology corresponds to the conception of soft chemistry and may be adapted to the manufacture of ultradispersed materials for catalysis, solar cells, fuel cells, semiconductors, sensors, low-sized electronic devices of new generation, etc.