Excellent electrochemical performance and CO2 tolerance of Fe-based tubule cathode catalysts for solid oxide fuel cells

In this work, a hollow tubule Bi0.8Ca0.2FeO3-delta (BCF-T) cathode was synthesized using the metal nitrate impregnation method, with absorbent cotton serving as the template. The phase composition, electrocatalytic activity performance, oxygen reduction reaction (ORR) processes, and CO2 tolerance of the BCF-T cathode are systematically studied. Compared with ordinary powder BCF (BCF-P) cathode, the BCF-T cathode presents outstanding electrocatalytic activity for ORR. The polarization resistance of the BCF-T cathode is 0.06 Omega cm(2) at 700 degrees C, and the peak power density (PPD) of the single cell is 1042 mW cm(-2) at 800 degrees C. The unique tubular microstructure of BCF-T is beneficial for enhance the oxygen transport property and the ORR activity of the electrode. Moreover, the BCF-T electrode also shows excellent CO2 tolerance and chemical stability after 10% CO2 treatment at 700 degrees C for 10 h. These features indicates that the tubule electrode with superior electrocatalytic activity and CO2 tolerance might provide an effective strategy to design promising cathode catalysts for SOFCs.