SnO_x surface modified Sr₂Fe_1.5Mo_0.5O_6-δ cathode with enhanced electrocatalytic activities for direct CO₂ electrolysis...

Surface modification and/or reconstruction for perovskite oxides cathode is an efficient strategy to accelerate sluggish kinetics of CO₂ reduction reaction (CO2RR) in solid oxide electrolysis cells (SOECs). Herein, active SnO_x nanoparticles with average size of ∼10 nm are loaded on the surface of Sr₂Fe_1.5Mo_0.5O_6-δ (SFM) cathode via a facile wet infiltration method. Benefiting from improved specific surface area, expended three phase boundaries, optimized CO₂ adsorption/activation abilities, as well as additional oxygen vacancies, the as-prepared SOEC with the SFM@SnO_x cathode delivers an enhanced current density of 0.691 A cm^-2 under an applied voltage of 1.5 V at 850 °C for the CO₂ electrolysis, and successfully operates 100 h without any attenuation under 1.2 V at 800 °C. This work offers new insights into tailoring perovskite oxide cathode for the CO₂ electrolysis in SOEC via a surface post-treatment strategy.