Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, United States.
ACS Nano. 2013 May 28;7(5):3808-14. doi: 10.1021/nn303239e. Epub 2013 Apr 16.
Spatial localization of the oxygen reduction/evolution reactions on lanthanum strontium cobaltite (LSCO) surfaces with perovskite and layered perovskite structures is studied at the sub-10 nm level. Comparison between electrochemical strain microscopy (ESM) and structural imaging by scanning transmission electron microscopy (STEM) suggests that small-angle grain boundaries act as regions with enhanced electrochemical activity. The ESM activity is compared across a family of LSCO samples, demonstrating excellent agreement with macroscopic behaviors. This study potentially paves the way for deciphering the mechanisms of electrochemical activity of solids on the level of single extended structural defects such as grain boundaries and dislocations.
在亚 10nm 尺度上研究了具有钙钛矿和层状钙钛矿结构的镧锶钴氧化物（LSCO）表面上氧还原/演化反应的空间定位。电化学应变显微镜（ESM）与扫描透射电子显微镜（STEM）结构成像的比较表明，小角度晶界作为增强电化学活性的区域。ESM 活性在一系列 LSCO 样品中进行了比较，与宏观行为具有极好的一致性。这项研究为在单个扩展结构缺陷（如晶界和位错）水平上解析固体电化学活性的机制铺平了道路。
