Characteristics of Li2CO3 as sintering aid for Ce0.8Sm0.2O2 electrolyte in solid oxide fuel cells

다국어 초록 (Multilingual Abstract)

Owing to its excellent ionic conductivity, 20 mol% samarium doped ceria (Ce0.8Sm0.2O2, SDC) is considereda promising alternative as an electrolyte in solid oxide fuel cells (SOFCs). SDC electrolytes, however, require highsintering temperatures over 1,600 oC to attain sufficient density to be SOFC electrolytes. To lower the SDC sinteringtemperature, different amounts of Li2CO3 (0-12mol% of Li) were evaluated as a sintering aid for SDC electrolytes. TheSDC electrolyte samples with Li were sintered at 1,400 oC and were compared with SDC electrolytes sintered at1,600 oC. The SDC electrolyte with 6mol% of Li sintered at 1,400 oC (Li6SDC1400) was densified to 97.495% of theoreticaldensity (T.D.), which is similar to that achieved by the SDC electrolyte sintered at 1,600 oC (97.433% of T.D.).
The improved formation of grain boundary in the Li6SDC1400 sample increased the density of the SDC, resulting inenhancement of ionic conductivity and cell performance. At 800 oC, the maximum power density of the Li6SDC1400electrolyte sample was 120.15mW/cm2.