La_0.75Sr_0.25Cr_0.5Mn_0.5O_3-δ as cathode for electrolysis and co-electrolysis of CO₂ and H₂O in solid oxide electrolysis cell

The cathode of solid oxide electrolysis cell (SOEC) is used as a place for fuel gas electrolysis/co-electrolysis, and its performance significantly affects the efficiency of electrolysis. La_0.75Sr_0.25Cr_0.5Mn_0.5O_3-δ (LSCM) is a potential SOEC cathode material due to its excellent redox stability and catalytic ability for fuel gas. An electrolyte-supported LSCM/YSZ/LSCM symmetrical cell and LSCM/YSZ/LSCF full cell were prepared and evaluated for high temperature steam electrolysis, carbon dioxide electrolysis and co-electrolysis. Under the applied voltage, both the symmetrical electrolysis cell and the full electrolysis cell can effectively electrolysis CO₂ and H₂O. During the experiment, by changing the operating conditions, the influence of different temperatures, concentration of CO₂ and H₂O, and applied voltage was studied to evaluate the electrochemical performance of SOEC. In order to further verify the long-term performance of SOEC, constant voltage was applied for co-electrolysis of CO₂ and H₂O. During the entire electrolysis process, the SOEC showed a stable current density of 0.1A·cm^-2 under the applied voltage 1.5 V for more than 24 h.