Effect of powder thermal treatment on the microstructure and electrical properties of doped ceria ceramics

Ce0.8Sm0.2O2 − δ electrolytes were prepared by sol–gel methods with different thermal treatment conditions. It was found that the particle size of the powders thermally treated in N2 could be controlled less than 10 nm, due to the fact that carbons that enwrapped the precursors could inhibit their crystallization. At the same time, the nano-sized precursors could form larger nuclei at the initial stage of sintering, resulting in the formation of electrolyte with higher density and larger grain size. At the same consent of oxygen vacancies, the enhancement of electrical properties for the electrolyte was correlated to its microstructure obtained by the N2 thermal treatment.