In situ construction of hetero-structured perovskite composites with exsolved Fe and Cu metallic nanoparticles as efficient CO2 reduction electrocatalysts for high performance solid oxide electrolysis cells

Abstract

Solid oxide electrolysis cells (SOECs) have been widely used for efficient conversion of CO₂ into valuable fuels and chemicals utilizing clean and renewable alternative energy sources. However, the scarcity of highly active cathode materials prevents their use in real-world applications. Herein, hetero-structured double perovskite/Ruddlesden–Popper perovskite (DP/RP-P) composites with exsolved Fe–Cu bimetallic nanoparticles are developed via in situ reduction treatment of the Sr₂Fe_1.25Cu_0.25Mo_0.5O_6−σ (SFCuM) perovskite at high temperatures. The LSGM-electrolyte-supported SOEC with the composite perovskites as the cathode demonstrates excellent electrochemical performance in CO₂ electrolysis. At an operating temperature of 800 °C and an applied potential of 1.4 V, the current density towards CO₂ electrolysis was as high as 1.7 A cm⁻², while the CO production and faradaic efficiency achieved were about 12.8 ml min⁻¹ cm⁻² and 95.2%, respectively. These results indicate that the hetero-structured DP/RP-SFCuM composites with exsolved Fe–Cu bimetallic nanoparticles are promising CO₂ electrolysis electrocatalysts for high-performance SOECs. Our research therefore highlights the potential for developing extremely efficient electrocatalysts for CO₂ electrolysis and utilization.