原位即時觀察單壁奈米碳管薄膜成長過程之研究

HASH(0x1c131be0)

梁家榮(Jia-Rong Liang)

指導教授 ： 戴念華

國立清華大學/工學院/材料科學工程學系/碩士(2008年)

https://doi.org/10.6843/NTHU.2008.00485

摘要

本實驗以垂直式流動觸媒法成長單壁奈米碳管，研究在此系統中單壁奈米碳管薄膜的生長過程。以原位即時攝影觀察到，在奈米碳管的成長過程中會伴隨著氣溶膠的生成。經由一系列不同實驗參數的觀察結果，推定此氣溶膠的生成是由於催化劑前驅物二茂鐵在高溫爐管中裂解還原成鐵原子，並進一步聚集形成奈米級的鐵團簇或是與其本身裂解的碳反應形成奈米碳管，而展現出氣溶膠的形態。
另一方面，本實驗進一步的利用數位相機所具有調變焦距的功能，藉由改變焦距面來觀察氣溶膠與奈米碳管薄膜在高溫爐管中所生成的區域，配合以熱電偶所量測到的爐管溫度分佈，可得知氣溶膠與奈米碳管薄膜生成的溫度範圍。將所有奈米碳管成長結果加以歸納整理，可對使用流動觸媒法成長單壁奈米碳管提出一套較完整的成長模型。

關鍵字

單壁奈米碳管 ； 流動觸媒法

並列摘要

In this study, the vertical floating catalyst method was adopted to synthesize single-walled carbon nanotubes (SWCNTs) and to investigate the growth mechanism of the SWCNTs film. During the synthesis process, formation of the aerosol was in-situ observed. Furthermore, based on the experiment results, it was verified that the aerosol was synthesized due to the pyrolysis of ferrocene. It was concluded that ferrocene was decomposed at high temperature region of the furnace to form iron clusters due to collision in the floating gas. Besides, decomposition of hydrocarbon rings of ferrocene also contribute carbon source for CNT growth.
Moreover, we used the digital camera with focal tunable to observe the locations of aerosol generation and SWCNTs film formation. Base on the furnace temperature distribution measured by thermocouple, the temperatures for aerosol and SWCNTs film formation were proposed. Furthermore, a model for SWCNT growth in the floating catalyst method was suggested.

並列關鍵字

SWCNT ； the floating catalyst method

參考文獻

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