Evaluation of lanthanum ferrite coated interconnect for intermediate temperature solid oxide fuel cells

In this paper, an La0.8Sr0.2FeO3−δ (LSF20) protective layer has been prepared on SUS430 alloy substrate using the atmospheric plasma spraying technology combined with nitrate solution impregnation and its effectiveness was evaluated. Thermodynamic and electrochemical performance tests confirmed the effectiveness of the LSF20 protective layer for decreasing the oxidation rate of the alloy and abating the chromium poisoning to the cathode. Upon exposure to air at 800 °C for 100 h, the oxidation rate of LSF20-coated alloy was reduced 56 folds compared to that of the uncoated alloy, and the LSF20-coated alloy produced a low area specific resistance of 1 mΩ cm2 after oxidized in air at 800 °C for 1000 h. Half-cell measurement results indicate that the influence of chromium poisoning on the La0.8Sr0.2MnO3−δ cathode was greatly inhibited with the LSF20-coated SUS430 alloy as interconnects.