物理化学学报 >> 2012, Vol. 28 >> Issue (07): 1790-1796.doi: 10.3866/PKU.WHXB201204174

材料物理化学 上一篇    下一篇

超声分散对单壁碳纳米管分离的影响

檀付瑞1,2, 李红波1, 桂慧1, 张静1, 李儒1, 金赫华1   

  1. 1. 中国科学院苏州纳米技术与纳米仿生研究所, 江苏苏州 215125;
    2. 中国科学院研究生院, 北京 100049
  • 收稿日期:2012-02-22 修回日期:2012-04-17 发布日期:2012-06-07
  • 通讯作者: 李红波 E-mail:hbli2008@sinano.ac.cn
  • 基金资助:

    国家重点基础研究发展规划项目(973) (2011CB932600)及国家自然科学基金(20903069, 21073223)资助

Effects of Ultrasonic Dispersion on the Separation of Single-Walled Carbon Nanotubes

TAN Fu-Rui1,2, LI Hong-Bo1, GUI Hui1, ZHANG Jing1, LI Ru1, JIN He-Hua1   

  1. 1. Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215125, Jiangsu Province, P. R. China;
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2012-02-22 Revised:2012-04-17 Published:2012-06-07
  • Contact: LI Hong-Bo E-mail:hbli2008@sinano.ac.cn
  • Supported by:

    The project was supported by the National Key Basic Research Program of China (973) (2011CB932600) and National Natural Science Foundation of China (20903069, 21073223).

摘要:

利用凝胶柱色谱技术, 研究者们通过两步或多步淋洗的方法实现了不同导电属性或电子结构单壁碳纳米管(SWCNTs)的分离, 并提出其分离机制主要是由不同导电属性和电子结构的SWCNTs 与凝胶填料之间作用力的差异所导致的. 基于凝胶柱色谱分离技术, 本文重点考察了超声时间对单壁碳纳米管单分散以及金属型/半导体型SWCNTs 分离的影响. 在一定的低超声功率下, 适当增加超声时间有利于SWCNTs 在十二烷基硫酸钠(SDS)溶液中的单分散. 紫外-可见-近红外(UV-Vis-NIR)吸收光谱、拉曼(Raman)光谱和荧光(PL)光谱表征结果表明, 2 h的超声条件是获得高纯度的金属型以及不同直径分布的半导体型SWCNTs 的最优条件. 我们认为不同超声时间对SWCNTs 分离的影响主要是改变了SWCNTs 的单分散性和长度, 调制了不同SWCNTs 与凝胶之间作用力的差异, 从而导致了不同SWCNTs分离结果.

关键词: 单壁碳纳米管, 凝胶柱色谱, 分散, 金属和半导体型分离, 超声时间

Abstract:

Recently, gel chromatography has been demonstrated as an effective method for the separation of single-walled carbon nanotubes (SWCNTs) according to their electronic type and structure. The separation of SWCNTs was thought to result from the different affinity forces between the gel and various SWCNTs. Based on this method, we investigated the effect of ultrasonic time on the dispersion and separation of metallic and semiconducting SWCNTs. At a low ultrasonic power, with the increase of ultrasonic time, better monodispersed SWCNTs in sodium dodecylsulfate (SDS) aqueous solution were obtained. The UV-visible-near infrared (UV-Vis-NIR) absorption, Raman and photoluminescence (PL) spectroscopic characterizations confirmed that under the condition of ultrasonication (2 h), higher-purity metallic tubes and semiconducting tubes with different diameter distributions could be obtained. We believe that the control of the ultrasonication time may tune the mono-dispersity and the length of SWCNTs, which would further influence the difference in affinity forces between various SWCNTs and the gel, therefore leading to different separation results.

Key words: Single-walled carbon nanotube, Gel column chromatography, Dispersion, Metal/semiconductor separation, Ultrasonic time