The production of carbon nanotubes (CNTs) by electric arc discharge (EA) usually applies pure mineral graphite (PMG) as the precursor electrode due to its high‐purity and conductivity. This work investigated the versatility of EA in aqueous medium for the production of CNTs by varying the electrodes purity degree. In this way, a variety of domestic and industrial graphite waste can be recycled into high‐quality CNTs by adjusting the EA parameters. CNTs were synthesized using 6B pencil (6BP, ~57% graphite) and their quality and quantity were compared to the PMG (99.995%) production. PMG led to short CNTs (I_D/I_G 0.266), while the synthesis with 6BP led to long CNTs (I_D/I_G 0.428). The 6BP CNTs showed elevated quality for application in the electronic, biomedical, and optical fields.

中文翻译：

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电弧在水性介质中环保合成MWCNTs：6B铅笔与矿物石墨的比较研究

由于电弧放电（EA）的高纯度和导电性，通常采用纯矿物石墨（PMG）作为前驱体电极来生产碳纳米管（CNT）。这项工作通过改变电极的纯度，研究了EA在水性介质中用于生产CNT的多功能性。通过这种方式，可以通过调整EA参数将各种家用和工业石墨废料回收为高质量的CNT。使用6B铅笔（6BP，〜57％石墨）合成CNT，并将其质量和数量与PMG（99.995％）的生产进行比较。PMG导致短的CNT（I _D / I _G 0.266），而6BP的合成导致长的CNT（I _D / I _G0.428）。6BP CNT在电子，生物医学和光学领域的应用显示出较高的质量。