Synthesis, Characterization and Performance of Calcium and Samarium Co- doped Ceria Electrolytes for Low and Intermediate Temperature Solid Oxide Fuel Cells

Three different compositions of samarium and calcium co-doped ceria were synthesized by cation- complexation process. The calcium content in co-doped Ce_0.8Sm_0.2-xCa_xO_2-δ varied from x=0.5 to 0.15. The effects of variation in calcium content on phase, crystallite size and morphology of the synthesized powders were investigated by XRD, SEM and TEM analyses. All synthesized powders were fluorite-type ceria nano-solutions. The particle size of Ce_0.8Sm_0.15Ca_0.05O_2-δ was around 10-17 nm as shown in fig.1. To evaluate the electrochemical behaviour the synthesized powders were die-pressed into pellets and sintered at 1450 °C for 10 hours. At 550°C, out of the three synthesized compositions, Ce_0.8Sm_0.15Ca_0.05O_2-δ showed the highest conductivity (0.013 S/cm). Anode-supported SOFCs with LSCF/Ce_0.8Sm_0.2-xCa_xO_{2- δ} /NiO-Ce_0.8Sm_0.2-xCa_xO_2-δ have been fabricated and tested for the purpose of investigating their potential use in low and intermediate temperature SOFCs.

Key words: Co-doped Ceria, SOFC.

References

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Key words: Co-doped Ceria, SOFC.