IONIC CONDUCTIVITY AND MICROSTRUCTURE OF CERIA-BASED POWDERS SYNTHESIZED BY GLYCINE COMBUSTION FOR SOFC
Keywords:
Ceria-based electrolyte, GDC, combustion, SOFCAbstract
Nanocrystalline Ce0.9Gd0.1O1.95 powders (GDC) have been successfully synthesized using combustion synthesis with metal nitrates as an oxidant and glycine as the fuel. X-ray diffraction patterns of the as-burnt GDC powders showed a single phase cubic fluorite structure. The crystalline size of the GDC powders increased with increasing the calcination temperatures. The densification and grain size of the GDC was found to increase when the sintering temperatures were increased from 1200-1350°C. Grain growth was observed after sintering at 1350°C, while the optimum densification and grain size was obtained after sintering at 1300°C. The grain interior and grain boundary conductivity related to the degree of densification and grain size of the sintered GDC electrolyte is discussed in this study.
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