本研究是以垂直式懸浮觸媒法製備單壁奈米碳管,主要是將碳源蒸氣與揮發後的金屬催化劑混合,在高溫下裂解反應形成奈米碳管。經由一系列製程參數的探討,可以成長出高純度的單壁奈米碳管,產量可達到每十分鐘40 ~ 200 mg。 另一方面,本實驗進一步在爐管後端加裝收集器及旋轉軸,目的在於有效收集成長之單壁奈米碳管,在嘗試水平式和垂直式轉軸之後,發現垂直式轉軸的收集方式遠優於水平式轉軸,單壁奈米碳管確實可纏繞於旋轉軸上,同時也探討轉軸上之奈米碳管其結構性質的變化。而在偶然的情況下,可以發現長條狀的奈米碳管束纏繞在旋轉軸上,將其取下做一個簡單的碳管吊重測試,結果顯示奈米碳管確實可吊起遠大於本身重量的物體,此長條束狀之碳管結構未來應用在纜繩等相關複合材料方面將具有一定的潛力。
In this study, we used vertical floating catalyst method to produce single-walled carbon nanotubes. Carbon nanotubes were synthesized by pyrolyzing the vapor of carbon source mixed with sublimed metal catalysts at high temperature. After studying a series of experiment parameters, high purity single-walled carbon nanotubes with the production rate of 40~200 mg per ten minutes could be achieved. On the other hand, we progressively equipped the collector and rotator at the bottom of the thermal furnace in order to collect the grown single-walled carbon nanotubes effectively. In this work, the horizontal and the vertical rotators were tested. We found that the collection by the vertical rotator was far superior than that by the horizontal rotator, and single-walled carbon nanotubes were indeed spun on the rotator. The variation of structure and quality of carbon nanotubes collected by different rotators were also discussed. In an occasional condition, we found long CNTs bundles (about 30 cm) spun on the rotator. We took the CNTs bundles to hang an object simply, and the result showed that carbon nanotubes could really hang the object which was much heavier than themselves. The structure of long CNTs bundles will possess notable potential on the further application of the steel rope and related composite materials.