Niobium doped lanthanum calcium ferrite perovskite as a novel electrode material for symmetrical solid oxide fuel cells

Development of cost-effective and efficient electrochemical catalysts for the fuel cells electrode is of prime importance to emerging renewable energy technologies. Here, we report for the first time the novel La_0.9Ca_0.1Fe_0.9Nb_0.1O_3−δ (LCFNb) perovskite with good potentiality for the electrode material of the symmetrical solid oxide fuel cells (SSOFC). The Sc_0.2Zr_0.8O_2−δ (SSZ) electrolyte supported symmetrical cells with impregnated LCFNb and LCFNb/SDC (Ce_0.8Sm_0.2O_2−δ) electrodes achieve relatively high power outputs with maximum power densities (MPDs) reaching up to 392 and 528.6 mW cm⁻² at 850 °C in dry H₂, respectively, indicating the excellent electro-catalytic activity of LCFNb towards both hydrogen oxidation and oxygen reduction. Besides, the MPDs of the symmetrical cells with LCFNb/SDC composite electrodes in CO and syngas (CO: H₂ = 1:1) are almost identical to those in H₂, implying that LCFNb material has similar catalytic activities to carbon monoxide compared with hydrogen. High durability in both H₂, CO and syngas during the short term stability tests for 50 h are also obtained, showing desirable structure stability, and carbon deposition resistance of LCFNb based electrodes. The present results indicate that the LCFNb perovskite with remarkable cell performance is a promising electrode material for symmetrical SOFCs.