A robust fluorine-containing ceramic cathode for direct CO_(2) electrolysis in solid oxide electrolysis cells  

作　　者：Shaowei Zhang Chengyue Yang Yunan Jiang Ping Li Changrong Xia 

机构地区：[1]CAS Key Laboratory of Materials for Energy Conversion,Department of Materials Science and Engineering,University of Science and Technology of China,Hefei 2300026,Anhui,China [2]School of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,Jiangsu,China [3]Energy Materials Center,Anhui Estone Materials Technology Co.Ltd,Hefei 230088,Anhui,China

出　　处：《Journal of Energy Chemistry》2023年第2期300-309,I0008,共11页能源化学（英文版）

基　　金：supported by the National Key R&D Program of China(2021YFB4001401);the National Natural Science Foundation of China(51972298)。

摘　　要：Stro ntium-doped lanthanum ferrite(LSF)is a potential ceramic cathode for direct CO_(2) electrolysis in solid oxide electrolysis cells(SOECs),but its application is limited by insufficient catalytic activity and stability in CO_(2)-containing atmospheres.Herein,a novel strategy is proposed to enhance the electrolytic performance as well as chemical stability,achieved by doping F into the O-site of the perovskite LSF.Doping F does not change the phase structure but reduces the cell volume and improves the chemical stability in a CO_(2)-rich atmosphere.Importantly,F doping favors oxygen vacancy formation,increases oxygen vacancy concentration,and enhances the CO_(2) adsorption capability.Meanwhile,doping with F greatly improves the kinetics of the CO_(2) reduction reaction.For example,kchem increases by 78%from3.49×10^(-4) cm s^(-1) to 6.24×10^(-4) cm s^(-1),and Dchem doubles from 4.68×10^(-5) cm^(2) s^(-1) to 9.45×10^(-5)cm^(2) s^(-1).Consequently,doping F significantly increases the electrochemical performance,such as reducing R_(p) by 52.2%from 0.226Ωcm^(2) to 0.108Ωcm^(2) at 800℃.As a result,the single cell with the Fcontaining cathode exhibits an extremely high current density of 2.58 A cm^(-2) at 800℃and 1.5 V,as well as excellent durability over 200 h for direct CO_(2) electrolysis in SOECs.

关 键 词：Solid oxide electrolysis cell CO_(2)electrolysis Ceramic cathode F doping Strontium-doped lanthanum ferrite 

分 类 号：O646.541[理学—物理化学] TM91[理学—化学]