...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Applied Physics >Dynamic modeling of carbon nanofiber growth in strong electric fields via plasma-enhanced chemical vapor deposition
【24h】

Dynamic modeling of carbon nanofiber growth in strong electric fields via plasma-enhanced chemical vapor deposition

机译：通过等离子体增强化学气相沉积在强电场中碳纳米纤维生长的动态模型

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Plasma enhanced chemical vapor deposition is an important method in the synthesis of carbon nanofibers which have been widely used in many technologies. Previous work devoted to the theoretical modeling of this process focused only on kinetics, i.e., the steady-state growth rate and its dependence on experimental conditions. This paper develops a dynamic model of a single carbon nanofiber grown in the cathode layer of a weakly ionized C2H2 glow discharge plasma. The model takes into account all main processes, including chemical kinetics, heat transfer, and the dynamics of electric field distribution. Specifically, the model considers the effects of a strong electric field on nanofiber growth: the field enhanced neutral particle flux and heat flux toward the catalyst and the increased catalyst temperature as a result of the thermal field emission current (along with its accompanying Nottingham effect). Numerical simulation shows that the increased fluxes caused by a strong electric field are unlikely to lead to a substantial acceleration of nanofiber growth. The growth tends to saturate, up to a complete stop, caused by the catalyst heating, which starts around the same time the field enhanced fluxes become significant. This serves as an alternate termination mechanism of nanofiber growth to the commonly-known catalyst poisoning. The competition and transition of the two mechanisms when changing the characteristic time of catalyst poisoning are shown. The results of this work help to improve the physical understanding of nanofiber growth and lay the foundation for further studies on other types of plasma-assisted nanofabrication. Published under license by AIP Publishing.
机译：等离子体增强化学气相沉积是合成碳纳米纤维的一种重要方法，碳纳米纤维已被许多技术广泛使用。先前致力于该过程的理论模型的工作仅关注动力学，即稳态生长速率及其对实验条件的依赖性。本文建立了在弱电离的C2H2辉光放电等离子体的阴极层中生长的单碳纳米纤维的动力学模型。该模型考虑了所有主要过程，包括化学动力学，热传递和电场分布动力学。具体而言，该模型考虑了强电场对纳米纤维生长的影响：由于热场发射电流（伴随其伴随的诺丁汉效应），该场增强了朝向催化剂的中性粒子通量和热通量，并提高了催化剂温度。 。数值模拟表明，由强电场引起的通量增加不太可能导致纳米纤维生长的显着加速。由催化剂加热引起的增长趋于饱和，直至完全停止，这大约在磁场增强的通量变得显着的同时开始。这充当了纳米纤维生长到通常已知的催化剂中毒的另一种终止机制。当改变催化剂中毒的特征时间时，显示了两种机理的竞争和转变。这项工作的结果有助于增进对纳米纤维生长的物理理解，并为进一步研究其他类型的等离子体辅助纳米制造奠定基础。由AIP Publishing授权发布。

著录项

  • 来源
    《Journal of Applied Physics》 |2019年第20期|203304.1-203304.9|共9页
  • 作者

    Zhang Xuewei; Shneider Mikhail N.;

  • 作者单位

    Texas A&M Univ Kingsville, Frank H Dotterweich Coll Engn, Kingsville, TX 78363 USA;

    Princeton Univ, Dept Mech & Aerosp Engn, Princeton, NJ 08544 USA;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号