Synthesis and densification of nanometric Ce_0.8Sm _0.2O_1.9-δ

Nanometric 20% molar Sm-doped ceria (SDC20) powders were synthesized by N, N, N', N' Tetramethylethylendiamine (TMEDA) co-precipitation method. SDC20 was sintered in several conditions to control the final microstructure. Fast firing and conventional sintering were performed and LiNO₃ was used as an additive to promote liquid phase sintering of ceria at low temperatures (900-1200°C). Powders and dense pellets were analysed using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). Electrochemical impedance spectroscopy (EIS) measurements were performed on dense pellets in air to estimate the contribution of grain boundary and bulk to the electrical conductivity. Liquid phase sintering produced the densest samples with the highest conductivity.