Structural and Electrical Properties of Gd Doped CeO2 (GDC) Nanoceramics for Solid Oxide Fuel Cell Applications

In the present work, gadolinium doped ceria (Gd0.1Ce0.9O2-δ, GDC) is prepared via sol-gel technique. The as-prepared samples are calcined at different temperatures followed by sintering at various temperatures to obtain uniform microstructure and dense samples. The most uniformly distributed grains with less porosity are obtained for sintered samples at 1450°C for 6 h with an average grain size of 0.85 μm. Single-phase cubic fluorite structure is confirmed by X-ray diffraction analysis. Conductivity analysis reveals that GDC exhibited conductivity around 4.6 × 10−3 S.cm−1 at 550°C. The activation energy of 1.01 eV indicates that ions dominate the conduction, which is best for SOFC electrolytes. This conductivity has been achieved at lower sintering temperatures (1450°C) than the solid-state reaction method (1600°C).