中文摘要：

以乙醇为碳源，二茂铁为催化剂，氮气为电弧工作气体，利用等离子体射流在常压下制备高纯度竹节状多壁碳纳米管。用TEM和HRTEM等技术对所得产品进行表征。发现在电弧电压140V～150V，电流220A～240A，将二茂铁和乙醇混合溶液（质量比为1：100）以50mL／min速度连续加入反应器，反应120S后，即可批量制备纯度在90％以上的竹节状碳纳米管；这些竹节状碳纳米管的管径尺寸均匀，为20nm左右，长度为数微米，其管壁呈典型的鱼骨状。产品中含有部分分叉结构，呈Y形竹节状碳纳米管。认为竹节状碳纳米管的形成涉及以下几个步骤：乙醇在等离子体射流中裂解产生大量碳活性物种，同时溶解在乙醇中的二茂铁生成催化剂颗粒：碳活性物种在催化剂颗粒上溶解、扩散并从催化剂颗粒上析出堆积成为碳纳米管管壁碳层，由于催化剂颗粒运动与碳层生长速度的差异，最终形成竹节状结构的碳纳米管。

英文摘要：

Bamboo-shaped carbon nanotubes （BCNTs） were synthesized continuously in high yields from ethanol in an arc plasma jet under atmospheric pressure with ferrocene as catalyst. The products obtained were characterized by TEM and HRTEM. The typical arc plasma conditions for the mass production of BCNTs at atmos- pheric pressure that can be achieved in about 120 s are direct current, 220-240 A; voltage, 140- 150 V; the in- jecting rate of ethanol and ferrocene mixture （ 100：1 by weight）, 50 mL/min. It was found that the as-prepared BCNTs with a fishbone-type wall exist in an entangled state and have a uniform outer diameter of ca. 20 nm and a length of several microns. The purity of BCNTs in the final product is estimated to be over 90 %. BCNTs with branched morphologies are also observed occasionally. It is believed that several steps are involved in the growth of BCNTs. Once the mixture of ethanol and ferrocene is injected into the arc plasma reactor, ethanol undergoes decomposition reactions, releasing a large amount of active carbon species that work as the building blocks of BCNTs. At the same time, ferrocene is decomposed, yielding aggregated Fe particles that function as a catalyst for the growth of BCNTs. Active carbon species are immediately adsorbed by or dissolved inside the catalyst particles formed in situ, and graphene layers nucleate on the surfaces of the catalyst particle and finally grow into bamboo-shaped tubular structures because of the diffusion of carbon species inside the catalyst particles, and more importantly because of the difference in the mobilities of the catalyst particles and the graphitic shell.