Studies on mechanism of single-walled carbon nanotube formation
Studies on mechanism of single-walled carbon nanotube formation
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DOI：
10.1166/jnn.2006.340
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发表时间：
2006-05-01
影响因子：
--
通讯作者：
Kauppinen, Esko I.
中科院分区：
文献类型：
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作者：
Nasibulin, Albert G.;Queipo, Paula;Kauppinen, Esko I.
我们提出了详细的研究单壁碳纳米管的形成气溶胶方法的基础上引入的预形成的催化剂颗粒的条件下，导致碳纳米管的合成。一氧化碳和铁纳米粒子分别用作碳源和催化剂。蚀刻剂，如CO2和H2O在CNT形成的重要作用，证明了在线傅立叶变换红外光谱测量的基础上。氢被证明参与碳释放的反应，并防止催化剂颗粒和热线的氧化。H2和少量CO2和H2O的加入导致碳纳米管长度的增加。发现反应器内的催化剂颗粒蒸发过程在高于1100 ℃的温度下变得显著。通过原位取样发现碳纳米管生长在反应器的加热部分中在约900 ℃的温度下发生，并且生长速率计算为超过1.1 μ m/s。详细分析了碳纳米管形成过程中可能的过程，发现七边形转化是一个限制性阶段。提出了碳纳米管的形成机理。
We presented detailed studies of the formation of single-walled carbon nanotubes by an aerosol method based on the introduction of pre-formed catalyst particles into conditions leading to carbon nanotube synthesis. Carbon monoxide and iron nanoparticles were used as a carbon source and a catalyst, respectively. The vital role of etching agents such as CO2 and H2O in CNT formation was demonstrated on the basis of on-line Fourier-transform infrared spectroscopy measurements. Hydrogen was shown to participate in the reaction of carbon release and to prevent the oxidation of the catalyst particles and the hot wire. The addition of H-2 and small amounts of CO2 and H2O led to an increase in the carbon nanotube lengths. The catalyst particle evaporation process inside the reactor was found to become significant at temperatures higher than 1100 degrees C. The carbon nanotube growth was found to occur at a temperature of around 900 degrees C in the heating section of the reactor by in situ sampling and the growth rate was calculated to exceed 1.1 mu m/s. A detailed analysis of possible processes during carbon nanotube formation revealed heptagon transformation as a limiting stage. A mechanism for carbon nanotube formation was proposed.