Surface tuned La0.9Ca0.1Fe0.9Nb0.1O3-δ based anode for direct methane solid oxide fuel cells by infiltration method

It has been found in our previous study that La 0.9 Ca 0.1 Fe 0.9 Nb 0.1 O 3-δ -Sm 0.2 Ce 0.8 O 1.9 (LCFNb-SDC) anode shows high catalytic activity and stability for solid oxide fuel cells (SOFCs) under H 2 and CO atmospheres. In this study, LCFNb-SDC is further tuned into a promising anode for direct methane SOFCs through surface modification with Ni. The LCFNb, SDC and Ni materials are found to be thermal-mechanically and chemically compatible with each other up to 850   °C. Although LCFNb-SDC anode shows poor catalytic activity for methane oxidation , further modification of such anode with a small amount of Ni particles significantly improves the cell performance in CH 4 . The maximal power densities of 1031 and 729   mW   cm −2 in H 2 and CH 4 have been achieved for the electrolyte supported SOFC with LCFNb-SDC-Ni|SSZ (Sc 0.2 Zr 0.8 O 2−δ )|LSM (La 0.8 Sr 0.2 MnO 3 ) configuration at 850   °C, respectively. Besides, the same cells also exhibit good stabilities in both H 2 (500   h) and CH 4 (100   h) with no obvious performance degradation and carbon deposition. Surface tuned LCFNb anode by impregnating SDC and a small amount of Ni is thus highly promising as an anode for direct methane SOFCs to deliver favorable performance with reasonable stability.