Boosting direct-ethane solid oxide fuel cell efficiency with anchored palladium nanoparticles on perovskite-based anode

Abstract

An efficient anode catalyst for hydrocarbon fuel in Solid Oxide Fuel Cells (SOFC) should possess a stable phase structure, high catalytic efficiency, and excellent coke resistance. However, traditional nickel-based anodes necessitate high steam-to-carbon ratios to prevent coking, complicating system design and reducing the overall performance. In this work, we report a nickel-free PrBaFe_1.9Pd_0.1O_5+δ perovskite as anode material for direct ethane SOFC, which demonstrates superior electroactivity and chemical stability. Under a reducing atmosphere, Pd nano-catalysts exsolved in-situ are uniformly anchored to the perovskite surface. Density functional theory analyses reveal that the Pd exsolution significantly improve ethane adsorption capacity, thereby reducing activation resistance and boosting catalytic performance. When used as an anode for an SDC electrolyte-supported SOFC, superior performance is achieved with the peak power densities (PPDs) of 702 and 377 mW cm^-2 at 800 °C when using hydrogen and almost dry ethane (3% H₂O) as fuel, respectively. Moreover, the cell exhibits a stable continuous operation over 90 h under almost dry ethane atmosphere at 178 mA cm⁻², presenting a promising pathway for developing high-performance, nickel-free SOFC anodes that simplify system design and improves efficiency when operating with hydrocarbon fuels, thus holding significant potential for practical SOFC applications.