Improved CO₂ electrolysis by a Fe nanoparticle-decorated (Ce, La, Sr)(CrFe)O_3-δ perovskite using a combined strategy of lattice defect-building

Application of solid oxide cell in CO₂ electrolysis is still restricted due to the insufficient electrocatalytic activity. Herein, a Fe nanoparticle-decorated (Ce, La, Sr)(CrFe)O_3-δ perovskite (Fe-CLSCF) was obtained by reducing the A-site deficient (Ce_0.08La_0.52Sr_0.3)Cr_0.5Fe_0.5O_3-δ. Activity of Fe-CLSCF as the cathode material for solid oxide reversible cells was investigated. In CO₂ electrolysis mode, the cell shows high current density of 2.21 A cm⁻² and high faraday efficiency of 97.2% at 850 °C and 2.0 V in CO₂/CO (70:30) fuel. The cell displayed excellent durability over a period of 106 h at above 1 A cm⁻². In the SOFC mode, the peak power density of 188 mW cm⁻² was achieved at 850 °C in CO₂/CO (70:30) fuel. Experiments and DFT calculation indicate that the perovskite materials with more oxygen vacancies are more likely to adsorb and activate CO₂. The combined strategy of lattice defect-building promotes the chemical adsorption/activation and surface reaction kinetics of CO₂, which consequently enhances the electrolysis performance.