Journal of Power Sources, Vol.179, No.1, 96-100, 2008
Substituted Sr2MnO4 as a possible cathode material in SOFC
Sr2-xLaxMnO4+delta (x = 0.4, 0.5, 0.6) oxides were studied as the cathode material for solid oxide fuel cells (SOFC). The reactivity tests indicated that no reaction occurred between Sr2-xLaxMnO4+delta and CGO at annealing temperature of 1000 degrees C, and the electrode formed good contact with the electrolyte after being sintered at 1000 degrees C for 4 h. The total electrical conductivity, which has strong effect on the electrode properties, was determined in a temperature range from 100 to 800 degrees C. The maximum value of 5.7 S cm(-1) was found for the x = 0.6 phase at 800 degrees C in air. The cathode polarization and AC impedance results showed that Sr1.4La0.6MnO4+delta,6 exhibited the lowest cathode overpotential. The area specific resistance (ASR) was 0.39 Omega cm(2) at 800 degrees C in air. The charge transfer process is the rate-limiting step for oxygen reduction reaction on Sr1.4La0.6MnO4+delta electrode. (c) 2007 Elsevier B.V. All rights reserved.