Preparation and electrochemical properties of LaBiMn2O6 cathode for IT-SOFCs
Résumé
LaBiMn2O6 (LBM) cathode for IT-SOFCs (intermediate temperature solid oxide fuel cells) has been prepared by solid state reaction and studied by XRD and EIS spectrum, respectively. The results show that LBM has no reaction with Ce0.7Bi0.3O1.85(CBO) electrolyte at 1 000 °C for 12 h. AC impedance spectroscopy and DC polarization measurements are used to study the electrode performances+ The polarization resistance decreases with temperature and reaches 0.71 Ω ·cm2 at 700 °C in air. Oxygen partial pressure study indicated that charge transfer process is the major rate limiting step for LaBiMn2O6 cathode from 600 to 700 °C. The LaBiMn2O6 cathode exhibits the lowest overpotential of 85 mV under current density of 216 mA ·cm-2 at 700 °C in air. This preliminary work showes that LaBiMn2O6 material may be potential cathodes for IT-SOFCs.