Defective structure of BN nanotubes: from single vacancies to dislocation lines.
Defective structure of BN nanotubes: from single vacancies to dislocation lines.
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DOI：
10.1021/nl061081l
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发表时间：
2006-07
期刊：
影响因子：
10.8
通讯作者：
A. Zobelli;C. Ewels;A. Gloter;G. Seifert;O. Stéphan;S. Csillag;C. Colliex
中科院分区：
文献类型：
--
作者：
A. Zobelli;C. Ewels;A. Gloter;G. Seifert;O. Stéphan;S. Csillag;C. Colliex
电子显微镜和理论计算的结合为 BN 单壁纳米管 (SWNT) 中点缺陷和空位线的结构、电子学和能量学提供了新的见解。我们表明，BN SWNT 中电子辐照下形成的点缺陷主要是双空位。由于 BN 键合的部分离子特性，双空位的行为类似于相关的肖特基对，解离能约为 8 eV。多个空位的聚集在能量上是有利的，并导致局部改变纳米管直径和手性的扩展缺陷。然而这些缺陷并没有显着改变带隙能量，并且它们都具有与BN双空位相似的电子结构。因此，我们得出结论，在辐照下，BN SWNT 的电子和光学特性可能会发生非常稳定的变化。
A combination of electron microscopy and theoretical calculations provides new insights into the structure, electronics, and energetics of point defects and vacancy lines in BN single-wall nanotubes (SWNT). We show that the point defects forming under electron irradiation in the BN SWNTs are primarily divacancies. Due to the partially ionic character of the BN bonding, divacancies behave like an associated Schottky pair, with a dissociation energy of around 8 eV. Clustering of multiple vacancies is energetically favorable and leads to extended defects which locally change the nanotube diameter and chirality. Nevertheless these defects do not alter significantly the band gap energy, and all of them have electronic structure similar to that of BN divacancies. We thus conclude that under irradiation BN SWNT may have a very stable alteration of its electronic and optical properties.