Electrolyte materials for solid oxide fuel cells derived from metal complexes: Gadolinia-doped ceria

Gadolinia doped ceria (GDC) powders with different gadolinium contents were successfully prepared by the thermal decomposition of ceria complexes. All the calcined powder samples were found to be ceria-based solid-solutions having a fluorite-type structure. The powders were cold-isostatically pressed and sintered in air at 1500 degrees C for 5 h to attain a sintered density of about 90% of its theoretical value. The electrical conductivity of the GDC pellets in air was studied as a function of temperature in the 225-700 degrees C range, by using two-probe electrochemical impedance spectroscopy measurements. The highest total conductivity (sigma(600 degrees C) = 0.025 S/cm) was found for the Ce0.85Gd0.15O1.925 composition. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved.