Enhancement of Conductivity in Ceria-Carbonate Nanocomposites for LTSOFCs

Abstract

This work first explores high resolution transmission electron microscopy (TEM) to determine the interfacial regions and provide experimental evidences for interfaces between the SDC and carbonate constituent phases of the SD-carbonate two-phase composites to further investigate the superionic conduction mechanism in the ceria-carbonate composite systems and enhancement of conductivity. Schober first reported interfacial superionic conduction in ceria-based composites but without direct experimental proofs. Such superionic conduction mechanism remains unknown. Especially, in the nano-scale, this region is trifle to be detected.

An intermediate temperature fuel cell based on composite electrolyte of carbonate and doped barium cerate with SrFe0.7Mn0.2Mo0.1O3−δ cathode

“…For the composite, the conductivity is in the range of 10 -6 S cm -1 at 300 °C but reached 0.28 S cm -1 at 500 °C. At 400 °C, the total conductivity of the composite is comparable to pure BCZYZn but the composite exhibits much higher conductivity at a temperature above 400 °C which could be related to the defects at the oxide/carbonate interface [29,30]. On the other hand, when the temperature approaches the melting point, the carbonates become 'soft'.…”