TiO_(2)诱导传统La_(0.5)Sr_(0.5)MnO_(3-δ)阴极电荷变化使其在质子导体固体氧化物燃料电池中展现出高性能  

TiO_(2)-induced electronic change in traditional La_(0.5)Sr_(0.5)MnO_(3−δ)cathode allows high performance of proton-conducting solid oxide fuel cells

作　　者：李玉凤 于守富 戴海璐 许阳森 毕磊 Yufeng Li;Shoufu Yu;Hailu Dai;Yangsen Xu;Lei Bi(School of Resource Environment and Safety Engineering,University of South China,Hengyang 421001,China;School of Materials Science and Engineering,Yancheng Institute of Technology,Yancheng 224051,China)

机构地区：[1]School of Resource Environment and Safety Engineering,University of South China,Hengyang 421001,China [2]School of Materials Science and Engineering,Yancheng Institute of Technology,Yancheng 224051,China

出　　处：《Science China Materials》2023年第9期3475-3483,共9页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (52272216 and 51972183);the Hundred Youth Talents Program of Hunan and the Startup Funding for Talents at the University of South China。

摘　　要：作为固体氧化物燃料电池(SOFC)最成功的阴极材料之一,Sr掺杂的LaMnO3材料在高温下表现良好.但其阴极活性随着工作温度的降低而剧烈下降,不适用于中温SOFC.本工作通过Ti O_(2)修饰传统La_(0.5)Sr_(0.5)MnO_(3-δ)(LSM)阴极形成LSM+TiO_(2)阴极.TiO_(2)可以改变LSM/TiO_(2)界面的电子结构,使得界面处氧原子发生电荷积聚,促进了氧空位的形成,从而提升了氧扩散能力.使用LSM+TiO_(2)阴极的质子导体SOFC (H-SOFC)的性能要明显高于单独使用LSM或者TiO_(2)阴极的性能,证明了LSM和TiO_(2)的协同效应.使用LSM+TiO_(2)阴极的H-SOFC单电池性能在700℃时达到1118 mW cm^(-2),是使用LSM基阴极的H-SOFC单电池性能的最高值.此外,LSM+TiO_(2)对CO_(2)和水蒸汽具有良好的稳定性,使其在工作中表现出良好的稳定性.LSM+TiO_(2)阴极的使用解决了传统LSM阴极在H-SOFC中性能较差的问题,同时保持了LSM基材料良好的稳定性.Sr-doped LaMnO3,as one of the most successful cathodes for solid oxide fuel cells(SOFCs),can effectively function at high temperatures.However,its cathode kinetics considerably decreases with decreasing temperature,rendering it unsuitable for SOFCs operating at intermediate temperatures.In this study,La_(0.5)Sr_(0.5)MnO_(3-δ)(LSM)is coated with TiO_(2) to create the LSM+TiO_(2) cathode.TiO_(2) is shown to modify the electronic structure at the LSM/TiO_(2) interface,allowing for charge accumulation for the O atoms at the interface.The activated O atoms enhance the formation of oxygen vacancies,which benefit the oxygen diffusion ability.Using LSM+TiO_(2) as a cathode for proton-conducting SOFCs(H-SOFCs)operating at intermediate temperatures,the corresponding fuel cell demonstrated enhanced cell output performance compared with cells employing solely LSM or TiO_(2) cathodes,exhibiting the synergistic effect of combining LSM and TiO_(2).Additionally,the LSM+TiO_(2) cells achieved a power output of 1118 mW cm^(−2) at 700℃,the highest yet reported value for H-SOFCs with LSM cathodes.LSM+TiO_(2) was demonstrated to be stable against CO_(2) and steam,allowing for steady functioning of the cell under working conditions,thereby resolving the problem of LSM’s poor performance in H-SOFCs while retaining remarkable stability.

关 键 词：质子导体 阴极材料 SOFC δ) 氧扩散 LAMNO3 电荷积聚 

分 类 号：TM911.4[电气工程—电力电子与电力传动] TQ133.3[化学工程—无机化工]