Preparation and sinterability of Ce_(0.8)Sm_(0.2)O_(1.9) powders by sol-gel and low temperature self-propagating synthesis

Ultrafine Ce0.8Sm0.2O1.9 (SDC) solid solution powders were prepared by the combination of sol-gel process and self-propagating low temperature combustion synthesis with glycine as reductant and metal nitrates as oxidant.The phase identification,morphology and specific surface area of SDC powders were investigated by XRD,SEM and BET method,respectively.The results showed that SDC powders calcined at 600℃ with crystallites in the 13—30 nm ranges had a pure cubic fluorite crystalline structure.It was found that the molar ratio of glycine to metal nitrate had a great effect on both the morphology and sinterability of the powders.When the molar ratio of glycine to metal nitrate was 2 and 3,the SDC powders possessed a loose structure.The powders had good sinterability in the experiment and the sintered specimens with relative density up to over 95% could be prepared by sintering at 1400℃ for 2 h.The average grain size of the sintered specimens was 0.5 μm.