Spark plasma sintering studies of nanosize lanthanide-doped ceria obtained by sot-gel method

Doped ceria powders, Ce-0.8 Ln(0.2)O(2-x) (Ln = Gd3+, Sm3+ and Yb3+) were sintered to nearly full density by Spark Plasma Sintering at 1100 and 1200 degrees C. The starting powders were obtained via a sol-gel method and had nanometric dimensions: 26.4 nm (Gd), 19.3 nm (Sm) and 31.4 nm (Yb). Samples characterization was performed by SEM, TEM and XRD to determine their structural and microstructural characteristics. The ionic conductivities of the sintered samples were determined by impedance measurements. The influence of the chemical composition, sintering temperature and microstructural characteristics on the total ionic conductivity were evaluated and discussed.