Enhancement of microplasma-based water-solubilization of single-walled carbon nanotubes using gas bubbling in water
Enhancement of microplasma-based water-solubilization of single-walled carbon nanotubes using gas bubbling in water
复制标题
DOI：
10.1088/0957-4484/18/33/335602
复制
发表时间：
2007-08-22
期刊：
影响因子：
3.5
通讯作者：
Suehiro, Junya
中科院分区：
文献类型：
--
作者：
Imasaka, Kiminobu;Kato, Yuki;Suehiro, Junya
作者以前提出了一种新的技术，用于制备水溶性碳纳米管（CNT）使用微等离子体产生的脉冲流光放电在水中。本文介绍了一种改进的方法，微等离子体为基础的碳纳米管增溶过程中使用的气体鼓泡在水中。氧气，氩气和氮气被用作鼓泡气体，以澄清的气体种类上的单壁碳纳米管（SWCNT）的增溶效率的影响。单壁碳纳米管悬浮液的紫外-可见吸收光谱表明，单壁碳纳米管的溶解度增加了两倍以上，通过使用气体鼓泡与微等离子体处理。在所测试的三种气体种类之间没有观察到显著差异。傅里叶变换红外光谱（FTIR）和X射线光电子能谱（XPS）分析表明，-OH基团的数量，引入单壁碳纳米管表面的微等离子体处理，增加了气体鼓泡。光发射测量还表明，由微等离子体产生的高度氧化的氧和氢自由基的数量也通过气体鼓泡而增加。这些结果表明，由于增强的自由基形成和单壁碳纳米管表面的官能化，气体鼓泡对基于微等离子体的单壁碳纳米管溶解具有积极影响。
The authors have previously proposed a novel technique for the preparation of water-soluble carbon nanotubes (CNTs) using microplasma generated by a pulsed streamer discharge in water. This paper describes an improvement in the method of the microplasma-based CNT solubilization process by the use of gas bubbling in water. Oxygen, argon and nitrogen were used as bubbling gas in order to clarify the effects of the gas species on the single-walled CNT (SWCNT) solubilization efficiency. Ultraviolet-visible absorption spectra of the SWCNT suspensions revealed that the SWCNT solubility was increased by more than two times by using gas bubbling together with microplasma treatment. No significant difference was observed among the three gas species tested. Fourier transform infrared (FTIR) spectroscopy and x-ray photoelectron spectroscopy (XPS) analysis showed that the number of -OH groups, introduced on the SWCNT surface by the microplasma treatment, was increased by gas bubbling. Optical emission measurements also showed that the number of highly oxidative oxygen and hydrogen radicals, which were generated by the microplasma, was also increased by gas bubbling. These results indicate that gas bubbling has positive effects on microplasma-based SWCNT solubilization as a result of enhanced radical formation and functionalization of the SWCNT surface.