Interfacial Dipole Enabled Three‐Dimensional Oxygen‐Exchange Network for Coking and Sulfur Tolerant Solid Oxide Cells

ABSTRACT Solid oxide cells (SOCs) are efficient for energy conversion and storage, but operation on hydrocarbons is limited by coking, sulfur poisoning, and slow surface kinetics. To address these challenges, we constructed a 3D oxygen‐exchange network that integrates Sr 1.9 Fe 1.5 Mo 0.43 Ru 0.07 O 6‐δ (SFMR), exsolved FeRu nanoalloy, and a continuous CeO 2 coating using an impregnation‐exsolution strategy. Within this oxygen‐exchange network, a vacancy‐rich ceria/perovskite interface hosts an interfacial dipole (FeRu←δ − | CeO 2 →δ + ) that couples exsolved FeRu to the Ce 4+ /Ce 3+ redox pair. This dipole‐driven charge redistribution enriches FeRu d states at the Fermi level (E F ) and strengthens O 2p‐d mixing, providing a unified lever to accelerate C─H and H─H bond activation and expedite oxygen delivery, aligning electronic conduction with oxygen‐exchange at a single interface. CeO 2 /SFMR fuel‐electrode‐based cells deliver peak power densities of 1.89 W cm −2 in H 2 and 1.63 W cm −2 in propane at 850°C, stable operation for 250 h in naphtha without coking and for 50 h in 50 ppm H 2 S‐H 2 , and 3.95 A cm −2 at 1.6 V for CO 2 electrolysis. These results define an efficient route to coking‐ and sulfur‐tolerant SOC fuel electrodes by pairing a d‐state‐rich exsolved alloy with a ceria oxygen shuttle in a 3D oxygen‐exchange network.