摘要
La1-xSrxCo1-yFeyO3系(LSCF)钙钛矿结构氧化物是一类性能优异的离子-电子混合导体,同时具有良好的化学稳定性和催化活性,有望作为中低温下工作的固体氧化物燃料电池阴极材料的候选材料.本文考察了La0.6Sr0.4Co1-yFeyO3(y=0.2~0.8)系材料的导电机制.XPS光电子能谱分析表明,除了存在小极化子导电机制外,同时还可能存在以下几种机理:1)热激发引起Co3+离子的电荷歧化;2)高温下氧空位生成导致的离子补偿;3)Fe4+较Co4+优先进行电荷补偿.
La1-xSrxCo1-yFeyO3 (LSCF) pcrovskite-type oxide is a wonderful electronic-ionic combine conductor and possesses, the characteristic of good chemical stability and catalyze activity, which can be used as a potential candidate for the cathode materials of Solid Oxide Fuel Cell ( SOFC). In this paper, the electrical conduction mechanism of La0.6Sr0.4Co1-yFeyO3( y = 0.2 - 0.8) cathode materials was studied. Analyses indicate that the electrical conduction appears to occur via a small-polaron hopping mechanism, In addition, the XPS results show that the other three factors: 1) the thermally activated disproportionation of Co^3+ ions into Co^2+ and Co^4+ pairs; 2) the ionic compensation of oxygen vacancies formed at high temperatures; 3) Fe^4+ ions electronic compensation preferential to Co^4+ , contribute to electrical conduction too.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2005年第6期902-904,共3页
Journal of Materials Science and Engineering
基金
南京理工大学科研发展基金资助项目(AB96055)