Counter Current Chromatography of Carbon Nanotubes

在过去的20年里，碳纳米管（CNT）由于其丰富的光学和电子特性而被吹捧为未来的材料。 可以具有单个、两个或多个碳壁，其中每个壁可以是半导体的或金属的，每个壁具有结构特定的光学转变，具有特殊的性质，例如高迁移率和环境稳定性，并且具有一定的长度范围。 然而，最初对CNT的兴奋很快就被抑制了，因为很明显，不可能以工业所需的数量选择性地合成任意定义结构（手性）的CNT。 合成后分离为该问题提供了解决方案，但是，这些技术的复杂性质加上小的量、低的产率、差的再现性、昂贵的化学品的使用和仅对小直径半导体CNT的容易的结构选择性继续阻碍CNT在最终用户应用中的出现。 该项目通过3个工作包（WP）为这些长期存在的问题提供了解决方案，这些工作包旨在将结构（手性）和对映体分类的CNT（大多数结构都有左手和右手品种）转化为廉价，大规模，易于大规模制备的材料，而无论其直径，壁数或电子类型如何。 在WP 1中，这将通过称为逆流色谱（CCC）的过程来实现，该过程将允许将CNT简单地注入到系统中并在几分钟内对CNT进行分类输出。 在WP 2中，CCC将允许表面活性剂条件的快速筛选，以将CNT分离扩展到大直径CNT物质，半导体和金属，沿着双壁和多壁CNT。 WP 3将为PEG/葡聚糖系统找到新的廉价水基替代品，并允许回收和再循环两相组分。 这将确保单壁碳纳米管的分离不仅是可扩展的，而且是便宜的，时间有效的和工业上有吸引力的。

For the last 20 years carbon nanotubes (CNTs) have been touted as a material for the future due to their richly varying optical and electronic properties. It is possible to have single, double or multiple carbon walls, where each wall can either be semiconducting or metallic, each possess structure specific optical transitions, have exceptional properties such as high mobilities and environmental stability and come in a range of lengths. However, the initial excitement for CNTs was quickly dampened as it became apparent that it was not possible to selectively synthesize CNTs of arbitrarily defined structure (chirality) in the quantities required by industry. Post synthesis separation offered a solution to this problem, but, the complicated nature of these techniques coupled with small quantities, low yields, poor reproducibility, the use of expensive chemicals and easy structure selectivity only to small diameter semiconducting CNTs continue to hinder the appearance of CNTs in end-user applications. This project provides a solution to these long-standing problems with 3 work packages (WPs) that are aimed at transforming structure (chirality) and enantiomer sorted CNTs (most structures come in both left- and right-handed varieties), regardless of their diameter, wall number or electronic type, into a material that is cheap, large scale, and easy to prepare at large scale. In WP1 this will be achieved with a process known as Counter Current Chromatography (CCC), which will allow for CNTs to be simply injected into a system and sorted CNTs output within minutes. In WP2, CCC will allow for rapid screening of surfactant conditions to extend CNT separation to large diameter CNT species, both semiconducting and metallic, along with double-walled and multi-walled CNTs. WP3 will find new cheap water-based alternatives to the PEG/dextran system and allow for recovery and recycling of the two-phase components. This will ensure that the separation of SWCNTs is not only scalable but also cheap, time effective and industrially attractive.