In Situ Exsolved Bimetallic Nanoparticles on Double Perovskite for Efficient CO 2 Electrolysis and Synergistic Methane Reforming in SOEC

Solid oxide electrolysis cells (SOECs) are promising energy conversion devices for the CO₂ reduction reaction (CO₂RR). However, their applications are limited by sluggish reaction kinetics and poor durability of the electrode. Herein, a hetero-structured (PrBa)_0.95Fe_1.5Cu_0.5O_6-δ with in situ formed FeCu bimetallic nanoparticles (FeCu@PB95FC) is designed to enhance CO₂ electrolysis and CH₄ reforming in SOECs. The current density of the cell with FeCu@PB95FC cathode achieves a remarkable current density of 1044.74 mA cm^-2 at 800 °C and 1.5 V for pure CO₂ electrolysis, with a CO production rate of 6.4 mL min^-1 cm^-2 and a Faraday efficiency of 95.23%. The superior electrocatalytic activity is attributed to the exsolved nanoparticles promoting electron transfer and additional oxygen vacancies generated within the perovskite substrate, providing numerous metal-oxide interfaces for gas adsorption and electrolysis. Furthermore, to reduce energy consumption of CO₂ electrolysis while generating value-added products, the symmetrical cell (FeCu@PB95FC|LSGM|FeCu@PB95FC) is synthesized, achieving a current density of 1.54 A cm^-2, alongside high syngas production (CO: 4.49 mL min^-1 cm^-2; H₂: 6.53 mL min^-1 cm^-2). This work offers a synergistic strategy for designing robust electrodes for efficient CO₂ conversion and methane utilization in SOECs, advancing sustainable energy technologies.