This work examines the electrical transport properties and electrode perfor
mance of two ceramic cathode materials (La0.84Sr0.16Co0.3Fe0.7O3 - LSCFe7 a
nd La0.84Sr0.16Co0.7Fe0.3O3 - LSCFe3) prepared by solid state reaction from
oxides and carbonates. Point-type electrodes pressed against the electroly
te material (GCO - Gd2O3 doped CeO2) were used to study the intrinsic perfo
rmance of these electrode-electrolyte combinations. Pt electrodes were also
used for comparison. For both ceramic cathodes a significant decrease in t
he cell ohmic contribution with increasing cathodic overpotentials suggests
that the electrochemical reaction spreads from the triple phase boundary l
ine to the electrode surface, a typical feature of mixed conducting electro
de materials. Overall, the steady state cathodic polarization measurements
performed at 800 degrees C showed the LSCFe3 sample to be the best cathode
material. LSCFe3 also had a higher conductivity than LSCFe7 (in the range 2
00 to 800 degrees C), thus showing an overall highly promising performance.
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