Characterization and performance of cobalt-free perovskite-type La0.6Ba0.4Fe0.8Ni0.2O3-delta cathode material for intermediate-temperature solid oxide fuel cells

摘要

A novel cobalt-free perovskite La0.6Ba0.4Fe0.8Ni0.2O3 - delta (LBFN) powder was synthesized using a combustion method. The phase composition, electrical conductivity, thermal expansion coefficient (TEC), and electrochemical properties of LBFN were systematically investigated. The X-ray diffraction (XRD) results revealed that LBFN had a high chemical compatibility with Ce0.8Sm0.2O2 - delta (SDC). The LBFN cathode exhibited a competitive electrode area-specific resistance (ASR) for the symmetric cell based on SDC electrolyte. Furthermore, the electrochemical performance of LBFN cathode could be effectively improved with the addition of the proper amount of SDC. Using the LBFN-SDC73 (7:3 in weight ratio) as a composite cathode, the Ni-SDC-supported single cell with a 25-mu m-thick SDC electrolyte exhibited maximum power densities of 330, 216, and 119 mW cm(-2) at 600, 550, and 500 A degrees C, respectively.