Exploring plasma mechanism of synthesis of the ultra-long single wall carbon nanotubes in arc discharge plasma

本研究的目的是研究电弧放电中等离子体合成超长单壁碳纳米管（SWNT）的机理。它们的刚度和韧性的结合使单壁碳纳米管成为已知最强的纤维。超长swnt（长度超过其直径的1万倍）有望实现微型电动机，并可作为有用的纳米级电缆用于导电或导热。大规模生产和使用将取决于对其合成背后的科学的理解。最近在电弧放电合成中发现，长度可能由磁场控制，这启发了一种可能的制造路线。本研究通过研究等离子体参数和产生的纳米管长度分布，旨在了解磁场的影响，并找到合成超长纳米管的最佳条件。本研究的主要区别在于，SWNT的合成问题将从合成的基本分析出发，而不是通过试错来解决。一种最新的朗缪尔探测技术将大大扩展大气电弧放电过程中等离子体参数的有限数据。电弧放电和等离子体与碳纳米管的相互作用将使用先前开发的流体代码进行建模。这个跨学科的项目既有基础意义又有技术意义。其根本意义在于对电弧放电和SWNT形成机理的认识将大大拓展。其技术意义在于探索控制SWNT合成的可能性，提高SWNT收率，最终为大批量生产和工业利用铺平道路。除了基础和技术意义之外，这项工作将作为纳米技术和等离子体科学领域的本科和研究生教育的优秀工具。为了让女性和未被充分代表的少数族裔参与进来，ppi将与乔治华盛顿大学的女工程师协会（Society of women Engineers）等学生组织密切合作。此外，本科生将参与研究。

0853777KeidarThe goal of this research is to study the plasma mechanism for synthesizing ultra-long single-wall carbon nanotubes (SWNT) in an arc discharge. Their combination of stiffness and toughness makes SWNTs the strongest known fibers. Ultra-long SWNTs (lengths more than 10,000 times larger than their diameters) are expected to enable micro-electric motors and can act as useful nanoscale cables for conducting electricity or heat. Mass production and use will depend on understanding the science behind their synthesis.A possible manufacturing route has been inspired by the recent finding that length might be controlled by a magnetic field in arc-discharge synthesis. The present research studies plasma parameters and the resulting nanotube length distribution, aiming both to understand the effect of the magnetic field and to find the best conditions for synthesis of ultra-long nanotubes. The main distinguishing factor of this study is that the problem of the SWNT synthesis will be approached from the basic analysis of synthesis and rather than by trial and error. A state-of-the-art Langmuir probe technique will significantly expand the limited data on plasma parameters during atmospheric arc discharge. The arc discharge and the plasma interactions with carbon nanotubes will be modeled using previously developed fluid codes. This interdisciplinary project has both fundamental and technological significance. The fundamental significance is that understanding of the arc discharge and SWNT formation mechanism will be greatly expanded. The technological significance lies in exploring the possibility of controlling SWNT synthesis, enhancing SWNT yield, and ultimately paving the way for mass production and industrial utilization. Beyond the fundamental and technological significance, this work will serve as an excellent vehicle for undergraduate and graduate education in the field of nanotechnology and plasma science. To involve women and under-represented minorities, the PIs will work closely with student organizations at George Washington like the Society of Women Engineers. In addition, undergraduate students will be engaged in the research.