Jia C L, Urban K
Institute for Solid State Research, Research Center Jülich, D-52425 Jülich, Germany.
Science. 2004 Mar 26;303(5666):2001-4. doi: 10.1126/science.1093617.
Using high-resolution imaging at negative spherical aberration of the objective lens in an aberration-corrected transmission electron microscope, we measure the concentration of oxygen in Sigma3[111] twin boundaries in BaTiO3 thin films at atomic resolution. On average, 68% of the boundary oxygen sites are occupied, and the others are left vacant. The modified Ti2O9 group unit thus formed reduces the grain boundary energy and provides a way of accommodating oxygen vacancies occurring in oxygen-deficient material by the formation of a nanotwin lamellae structure. The atomically resolved measurement technique offers the potential for studies on oxide materials in which the electronic properties sensitively depend on the local oxygen content.
在像差校正透射电子显微镜中，利用物镜负球差下的高分辨率成像，我们以原子分辨率测量了钛酸钡薄膜中Sigma3[111]孪晶界处的氧浓度。平均而言，68%的晶界氧位点被占据，其余为空位。由此形成的改性Ti2O9基团单元降低了晶界能，并通过形成纳米孪晶薄片结构提供了一种容纳缺氧材料中出现的氧空位的方式。这种原子分辨率测量技术为研究电子性质敏感依赖于局部氧含量的氧化物材料提供了可能性。
