La(Ni,Fe)O₃ as a cathode material with high tolerance to chromium poisoning for solid oxide fuel cells

A novel cathode material, La(Ni_0.4Fe_0.6)O₃ (LNF), is synthesized by a solid-state reaction for applications in solid oxide fuel cells (SOFCs). The electrochemical performance of the LNF cathode is investigated for the oxygen reduction reaction at 900°C in the presence of a Fe-Cr alloy interconnect, and compared with (La,Sr)MnO₃ (LSM) cathodes. Under these conditions, the LNF electrode has a more stable electrochemical activity than that of the LSM electrode. There is no deposition of chromium species on the electrode surface or at the LNF electrode|yttria-stabilized zirconia (YSZ) electrolyte interface after passage of 200 mA cm^-2 for 20 h at 900°C. By contrast, a significant amount of chromium species is preferentially deposited at the LSM|YSZ interface regions for the LSM electrode. The results demonstrate that the LNF electrode has high tolerance to chromium poisoning, and is, therefore, promising as a SOFC cathode when using chromia-forming alloy interconnects. © 2007 Elsevier B.V. All rights reserved.