Electric birefringence of carbon nanotubes: Single- vs double-walled
Electric birefringence of carbon nanotubes: Single- vs double-walled
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DOI：
10.1016/j.carbon.2017.10.001
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发表时间：
2018-01-01
期刊：
影响因子：
10.9
通讯作者：
Donovan, Kevin J.
中科院分区：
文献类型：
--
作者：
Arenas-Guerrero, Paloma;Jimenez, Maria L.;Donovan, Kevin J.
当受到外加电场的作用时，悬浮中的碳纳米管被极化并由于随之而来的电扭矩而被迫旋转。这种电子取向的分析不仅在基本层面上很有趣，而且还因为需要这些粒子排列的许多应用。此外，研究管子与电场的相互作用是一种信息量很大的非侵入性技术，能够提供关于它们微观性质的许多信息。为了监测粒子的取向，在这项工作中，我们测量了悬浮液的宏观光学各向异性，或称电双折射，当管子在场中定向时出现了这种各向异性。研究了两种类型的颗粒：单壁和双壁碳纳米管。通过较宽范围内电双折射的场特性，分析了悬浮管的电学、光学和几何特性。值得注意的是，研究发现，当单壁碳纳米管表现出正信号时，双壁碳纳米管表现出由反常光学各向异性引起的负双折射。(C)2017爱思唯尔有限公司。保留所有权利。
When subjected to an external electric field, carbon nanotubes in suspension are polarized and forced to rotate due to the consequent electric torque. The analysis of this electro-orientation is interesting not only at a fundamental level, but also because of the many applications that require the alignment of these particles. Moreover, the study of the interaction of the tubes with an electric field is a highly informative non-invasive technique, able to provide much information on their microscopic properties. In order to monitor the orientation of the particles, in this work we measured the macroscopic optical anisotropy of the suspension, or electric birefringence, that emerges when the tubes are oriented by the field. Two types of particle were studied: single-walled and double-walled carbon nanotubes. The electric, optical and geometrical properties of the suspended tubes were analysed via the field dependence of the electric birefringence over a wide range. Remarkably, it was found that, whilst single-walled carbon nanotubes show a positive signal, double-walled carbon nanotubes exhibit a negative birefringence caused by an anomalous optical anisotropy. (C) 2017 Elsevier Ltd. All rights reserved.