Thermochemical compatibility and polarization behaviors of La0.8Sr0.2Co0.8Ni0.2O3−δ as a cathode material for solid oxide fuel cell

• Cation exchange between LSCN and GDC was identified by XRD at 1150 °C for 10 h.
• LSCN performance seems reversible under anodic than cathodic current treatment.
• High and low frequency arcs of LSCN show different response to current treatment.

Thermochemical compatibilities with Ce0.8Gd0.2O2−δ (GDC) electrolyte and electrochemical behaviors under the condition of anodic or cathodic current treatment are investigated for La0.8Sr0.2Co0.8Ni0.2O3−δ (LSCN) cathode of solid oxide fuel cell (SOFC). X-ray diffractometer (XRD) shows that cation exchange at 1150 °C leads to the formation of solid state solution between the cathode and electrolyte. Considering thermal expansion coefficient (TEC) and conductivity, La1−xSrxCo1−yNiyO3−δ with the composition of La0.8Sr0.2Co0.8Ni0.2O3−δ is indicated as a promising cathode for intermediate temperature SOFC. Electrochemical measurement reveals that the performance of LSCN cathode shows reversibility under anodic with subsequent cathodic current treatment. Further, the low frequency electrode process is strongly affected by anodic current. While the high frequency arc shows independent relationship with current polarization.