Electrochemical performance, microstructure and chemical compositions of Cu-based nanoparticles driven by exsolution of CuFe₂O₄ in CO₂/H₂O and H₂O electrolysis

Use of perovskite as a cathode for solid oxide electrolysis cell is limited by its insufficient electrolysis current density or catalytic activity. Most of present perovskites used has a crucial drawback - significant segregation of A-site cations (i.e. SrO), likely resulting in the degradation of performance. In this work, spinel oxide of CuFe2O4, which is an alkline earth metal free oxide, is applied as the cathode material to investigate its electrochemical performance, microstructure and chemical composition in the electrolysis of CO₂/H₂O, steam and CO₂. It was found that the exsolution of Cu nanoparticles was observed in CO₂/H₂O co-electrolysis and the microstructure of CuFe₂O₄ influenced significantly by operating in different CO₂/H₂O compositions. Despite the significantly microstructural variation of the CuFe₂O₄ layer, the cell performs relatively stable electrochemical performance in CO₂/H₂O and steam electrolysis.