Electrochemical reduction of CO2 in a symmetrical solid oxide electrolysis cell with La0.4Sr0.6Co0.2Fe0.7Nb0.1O3-δ electrode

La0.4Sr0.6Co0.2Fe0.7Nb0.1O3-delta (LSCFN) perovskite oxide is investigated as electrode materials of a symmetrical solid oxide electrolysis cell (SOEC) for CO2 reduction reaction. A high current density of 0.442 A cm(-2) and a low polarization resistance are obtained @1.5 V with pure CO2 at 800 degrees C because of excellent CO2 adsorbability of LSCFN. When reducing carrier gas, such as CO and/or H-2 is flowed, the polarization resistance decreases further. Interesting, when H-2/CO contents increase, the current density firstly increases and then reaches a plateau, the behavior is different from the conventional Ni-cermet based SOEC. Due to the reverse water gas shift reaction when H-2 exists, the cell performance of CO2 electrolysis with H-2 as carrier gas is better than that with CO as carrier gas. The SOEC can be continuously operated for 150 h without any attenuation when H-2/CO2 = 3/7 mixture gas is filled @ 0.24 A cm(-2) at 800 degrees C. The study indicates that LSCFN is a promising electrode material for CO2 electrolysis.