温控电弧放电法大量制备单壁碳纳米管

采用可以控制真空室温度的改进型直流电弧炉，在氮气和氦气(1∶1)混合气氛下，使用Co-Ni(1∶1wt%)合金催化剂，通过控制温度等工艺条件，在容器内壁生成了大量单壁碳纳米管，尤其在阴极与阳极之间有大量的宏观网状薄膜.通过两步纯化方法：在500℃空气中烘烧30min；再用37%盐酸浸泡72h，用去离子水过滤至中性烘干.经SEM，HRTEM，XRD，Raman观察分析，纯化后其纯度高(>95％)、管径均匀(1.24—1.38nm).实验结果表明：温度强烈影响单壁碳纳米管的产量，不同温度下管子的纯度、产量都有差异，在温度为600℃时，其纯度达到70％，产量为12g/h. 关键词： 单壁碳纳米管 电弧法 温度影响

Large scale synthesis of single-walled carbon nanotubes by an arc-discharge method at controlled temperatures

Large amounts of single-wall carbon nanotubes(SWNTs) deposited on all the wall of the chamber have been obtained in helium and nitrogen mixed atmosphere using Co-Ni alloy catalyst with a modified arc furnace which can control the temperature during arcing process. Additionally, there are many web like deposition products located between the cathode and anode. By two step purification:the as-grown SWNT was heated in air at 500℃ for 30min, then soaked in 37% hydrochloric acid for 72h and filtered with deionized water. Microanalysis was carried out by Transmission electron microscopy(TEM), high-resolution TEM and Raman spectroscopy. The results obtained indicate that the purified SWNTs have high purity (higher than 95%) and uniform diameter (from 1.24 to 1.38nm).This experiment indicates that the temperature strongly affects the production of SWNT; the production and purity of SWNT increase with temperature. When the temperature is 600℃, the purity is about 70% and the production of SWNT is 12g/h.