BaCo0.4Fe0.4Zr0.2O3-δ: Evaluation as a cathode for ceria-based electrolyte IT-SOFCs

Zr-doped perovskite-type material BaCo0.4Fe0.4Zr0.2O3-δ (BCFZ) is prepared and systematically studied via X-ray diffraction (XRD) analysis, dilatometry and temperature-programmed desorption (TPD) of oxygen. The electrochemical performance of the BCFZ is characterized using electrochemical impedance spectroscopy (EIS) with symmetric cell configurations. BCFZ not only shows high oxygen reduction reaction (ORR) electro catalytic activity but also exhibits excellent compatibility with ceria-based (Ce0.8Sm0.2O1.9, SDC) electrolyte. They have a similar thermal expansion coefficient and no chemical reaction. With a BCFZ cathode, the SDC-based SOFC (Ni-SDC|SDC|BCFZ) shows high power densities (879 and 669 mW cm−2 at 650 and 600 °C, respectively). Moreover, it shows favorable stability in CO2-containing environment under SOFCs operating conditions.