Hierarchical heterostructure-driven high-efficiency co-generation of electricity and ethylene

FeCu-FeO x @SFCu 0.24 M-DP/RP enables ethylene–electricity cogeneration from ethane in oxide-ion-conducting SOFCs. • FeCu–FeO x promotes C–H bond activation and facilitates ethane dehydrogenation. • The cell achieves 78.4% ethane conversion and 81.7% ethylene selectivity at 750 °C. • Stable operation is sustained for 400 h with negligible performance degradation and coke deposition. Steam cracking of alkanes such as ethane accounts for over 90% of global ethylene production, but relies on energy-intensive, high-temperature pyrolysis, leading to significant carbon emissions and complex by-products that require costly purification. Enabling the co-generation of ethylene and electrical energy in oxide-ion-conducting solid oxide fuel cells (SOFCs), we design a highly selective anode for the electrochemical oxidative dehydrogenation of ethane (EOD-eth). The anode consists of a hierarchical heterostructure featuring oxygen-vacancy-rich FeCu-FeO x anchored onto a Sr 2 Fe 1.26 Cu 0.24 Mo 0.5 O 6-δ double-perovskite/Ruddlesden-Popper matrix (FeCu-FeO x @SFCu 0.24 M-DP/RP). The SOFCs demonstrate outstanding performance, maintaining CO 2 -free operation for over 400 h, while delivering a high-power density of 0.51 W cm −2 with an ethylene selectivity of 81.7% and an ethane conversion rate of 78.4% at 750 °C. Mechanistic investigations reveal that FeO x acts as both an effective oxygen-ion channel and an oxygen storage reservoir, activating ethane C–H bonds and promoting dehydrogenation, while FeCu enhances both ethylene selectivity and electronic conductivity. Beyond this specific reaction, the FeCu–FeO x –SFCu 0.24 M-DP/RP architecture embodies the essential attributes universally required of fuel electrode—including multivalent redox adaptability, robust structural resilience, and compatibility with diverse hydrocarbon or syngas fuels—thereby representing a broadly applicable catalytic platform for next-generation fuel-flexible SOFCs. Download: Download high-res image (176KB) Download: Download full-size image A hierarchical heterostructured composite anode is constructed by anchoring oxygen-vacancy-rich FeCu-FeO x onto a Sr 2 Fe 1.26 Cu 0.24 Mo 0.5 O 6-δ double-perovskite/Ruddlesden-Popper matrix, achieving superior electrochemical performance with a peak power density of 0.51 W cm −2 , an ethylene selectivity of 81.7%, and an ethane conversion of 78.4% at 750 °C.