期刊
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
卷 2, 期 7, 页码 801-807出版社
AMER CHEMICAL SOC
DOI: 10.1021/jz200160b
关键词
-
类别
资金
- US-DOE, Office of Fossil Energy [DE-NT0004117]
- Basic Energy Sciences [DE-SC0002633]
- National Science Foundation [TG-ASC090058]
Effects of strain on the surface cation chemistry and the electronic structure are important to understand and control for attaining fast oxygen reduction kinetics on transition-metal oxides. Here we demonstrate and mechanistically interpret the strain coupling to Sr segregation, oxygen vacancy formation, and electronic structure on the surface of La0.7Sr0.3MnO3 (LSM) thin films as a model system. Our experimental results from X-ray photoelectron spectroscopy and scanning tunneling spectroscopy are discussed in light of our first principles-based simulations. A stronger Sr enrichment tendency and a more facile oxygen vacancy formation prevail for the tensile-strained LSM surface. At 500 degrees C in 10(-3) mbar oxygen, both LSM film surfaces exhibit a metallic-like tunneling conductance, with a higher density of electronic states near the Fermi level on the tensile-strained LSM surface, contrary to the behavior at room temperature. Our findings illustrate the potential role and mechanism of lattice strain in tuning the reactivity of perovskite transition-metal oxides with oxygen in solid oxide fuel cell cathodes.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据