Building Efficient and Durable Hetero-Interfaces on a Perovskite-Based Electrode for Electrochemical CO2 Reduction

Solid oxide electrochemical cells (SOECs) have demonstrated the potential to be highly efficient devices for electrochemical CO2 reduction (CO2R) at intermediate temperatures. However, the performance and widespread applications for CO2R largely hinge on the sluggish reaction kinetics and poor durability of the state-of-the-art electrodes. Here, the findings in enhancing the reaction activity and durability of a perovskite-based electrode are reported, Sr2Fe1.5Mo0.3Cu0.2O6-delta (SF1.5MC), for electrochemical oxidation of H-2 and reduction of CO2. Under typical operating conditions, the SF1.5MC electrode is elegantly reconstructed into three phases of oxygen vacancy-rich double perovskite (DP), Ruddlesden-popper (RP), and Cu-Fe metals, as confirmed by X-ray diffraction and scanning transmission electron microscopy. When applied as a fuel electrode for an electrolyte-supported SOEC, decent performances are demonstrated at 800 degrees C, showing a maximum power density of 1.51 W cm(-2) in fuel cell mode (on H-2 fuel) and a current density of 1.94 A cm(-2) at 1.4 V in electrochemical CO2R to CO with high Faradaic efficiencies of approximate to 100% and good durability.

Automated summary

The findings report on a perovskite-based electrode SF1.5MC that enhances the reaction activity and durability for electrochemical oxidation of H-2 and reduction of CO2. Decent performances are demonstrated at 800 degrees C, with high power density and current density achieved.