Doped ceria with exsolved Fe0 nanoparticles as a Sr-free cathode for CO2 electrolysis in SOECs at reduced temperatures

Abstract

Fe-exsolved ceria is found to be highly efficient as a SOEC cathode for CO₂ electrolysis. Dopant Fe is partially reduced under working conditions, forming dispersed Fe⁰ nanoparticles, which remarkably enhances the catalytic activity for the CO₂ reduction reaction. At 700 °C, the cathode polarization resistance is 0.57 Ω cm², and the chemical surface exchange coefficient for CO₂ reduction is 1.68 × 10⁻³ cm s⁻¹, showing better performance than metal-exsolved perovskite cathodes at 800 °C.