Hydrothermal processes have the potential for the direct preparation of crystalline ceramic powders and offer a low-temperature alternative to conventional powder synthesis techniques in the production of oxide powders. These processes can produce fine, high-purity, stoichiometric particles of single and multi-component metal oxides. Furthermore, if process conditions such as solute concentration, reaction temperature, reaction time and the type of solvent are carefully controlled, the desired shape and size of particles can be produced. Uniform distribution of the particles is key for optimal control of grain size and microstructure in order to maintain high reliability. It has been demonstrated that such powders are composed of much softer agglomerates and sinter much better than those prepared by calcination decomposition of the same oxides. These powders could be sintered at low temperature without calcination and milling steps. The objective of this study was to synthesis TiO2-CeO2 nanosized crystalline particles by a hydrothermal process.TiO2-CeO2 nanosized powders were prepared under high temperature and pressure conditions by precipitation from metal nitrates with aqueous potassium hydroxide. The TiO2-CeO2 nanosized powder was obtained at 185°C and 6 h. The average size and size distribution of the synthesized particles were below 10±5 nm and narrow, respectively. The XRD diffraction pattern shows that the synthesized particles were crystalline. This study has shown that the synthesis of TiO2-CeO2 nanosized crystalline particles is possible under hydrothermal conditions in aqueous solution.
Micro-analytical studies of discontinuous precipitation in Fe-13.5 at.% Zn alloy
