A robust fuel cell operated on nearly dry methane at 500 degrees C enabled by synergistic thermal catalysis and electrocatalysis

Solid oxide fuel cells (SOFCs) are potentially the most efficient technology for direct conversion of hydrocarbons to electricity. While their commercial viability is greatest at operating temperatures of 300-500 degrees C, it is extremely difficult to run SOFCs on methane at these temperatures, where oxygen reduction and C-H activation are notoriously sluggish. Here we report a robust SOFC that enabled direct utilization of nearly dry methane (with similar to 3.5% H2O) at 500 degrees C (achieving a peak power density of 0.37W cm(-2)) with no evidence of coking after similar to 550 h operation. The cell consists of a PrBa0.5Sr0.5Co1.5Fe0.5O5+delta nanofibre-based cathode and a BaZr0.1Ce0.7Y0.1Yb0.1O3-delta-based multifunctional anode coated with Ce0.90Ni0.05Ru0.05O2 (CNR) catalyst for reforming of CH4 to H-2 and CO. The high activity and coking resistance of the CNR is attributed to a synergistic effect of cationic Ni and Ru sites anchored on the CNR surface, as confirmed by in situ/operando experiments and computations.