Investigation of Li Dopant as a Sintering Aid for ScSZ Electrolyte for IT-SOFC

다국어 초록 (Multilingual Abstract)

In this study, the effects of small amounts (≤3 mol%) of Li doping on the sintering characteristics and electrochemical
performance of (ZrO2)0.89(ScO1.5)0.1(CeO2)0.01 (ScSZ) were investigated. By adding 3 mol% lithium, the densification temperature of
ScSZ was reduced from the conventional temperature of 1400oC to 1200oC. It was found that Li doping also led to changes in the
Zr:Sc ratio at the grain boundaries. Correspondingly, the dispersion of lithium zirconia at the grain boundaries accelerated the
growth of ScSZ grains and increased the grain boundary resistance at temperatures below 450oC. At elevated temperatures of
450~750oC, the electrical conductivity of the ScSZ after doping remained almost unchanged under air and reducing atmospheres.
These results suggest that the addition of lithium is promising for use in low temperature co-firing of ScSZ-based components for
intermediate temperature solid oxide fuel cells.

다국어 초록 (Multilingual Abstract)

In this study, the effects of small amounts (≤3 mol%) of Li doping on the sintering characteristics and electrochemical
performance of (ZrO2)0.89(ScO1.5)0.1(CeO2)0.01 (ScSZ) were investigated. By adding 3 mol% lithium, the densification temperature of
ScSZ was reduced from the conventional temperature of 1400oC to 1200oC. It was found that Li doping also led to changes in the
Zr:Sc ratio at the grain boundaries. Correspondingly, the dispersion of lithium zirconia at the grain boundaries accelerated the
growth of ScSZ grains and increased the grain boundary resistance at temperatures below 450oC. At elevated temperatures of
450~750oC, the electrical conductivity of the ScSZ after doping remained almost unchanged under air and reducing atmospheres.
These results suggest that the addition of lithium is promising for use in low temperature co-firing of ScSZ-based components for
intermediate temperature solid oxide fuel cells.

참고문헌 (Reference)

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