以流動觸媒法於直立管爐中製作單壁奈米碳管之最佳化分析及機制探討

陳鑫錨(Hsin-Mao Chen)

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(2009年)

摘要

本實驗在一直立熱壁式管爐中以流動觸媒法成長單壁奈米碳管絨球，依田口法L18直交表設計規劃實驗，取拉曼光譜之ID/IG比值做為單壁奈米碳管的品質因素，最後得到了一組最佳化參數；並由變異數分析得知於本製程中，爐管溫度對碳管品質的貢獻率最大，其次為催化劑腔體溫度，然而爐管內壓力的變化則對碳管的品質影響不大。以最佳化參數組合為條件，經驗證實驗成長之單壁奈米碳管，其ID/IG比值為0.02，與預測的最佳化結果十分接近。
接著利用此最佳化參數成長長條狀奈米碳管束，藉由數位相機觀察長條狀奈米碳管束的形成過程並加以記錄，以提出可能的成長模型。所成長之長條狀奈米碳管束其長度長於30 cm，寬度約為0.8 cm﹔由FE-SEM影像及Raman光譜可知其主要是由許多單壁奈米碳管束準直排列而形成。

關鍵字

流動觸媒法 ； 單壁奈米碳管 ； 最佳化分析 ； 長條狀奈米碳管束

並列摘要

In this work, we studied the optimization of the growth parameters for synthesizing high quality fluffy single-walled carbon nanotubes in a vertically hot-walled furnace using the floating catalyst method. Taguchi analytical method was used to set the processing parameters by L18 orthogonal array. The ID/IG ratios of the Raman spectrum was selected as the quality index of the as-synthesized SWCNTs, and the optimum condition of the seven parameters could be determined. Furthermore, the quantitated contribution of the processing parameters could be obtained by performing the analysis of variance (ANOVA). Although almost all the seven parameters affect the growth of SWCNTs, the reaction temperature and the sublimation temperature of ferrocene influence the quality most obviously. The furnace pressure seems to be of minor importance to the quality compared with the other factors. The SWCNT fluff synthesized using the optimized parameters achieved superior quality (the ID/IG ratio was 0.02), which was similar to the predicted results using the Taguchi method.
Moreover, we produced CNT long strand using the optimized parameters. In-situ observation was recorded with a digital camera to find a growth mechanism of the CNT long strand. The CNT long strand was longer than 30 cm with about 0.8 cm in width. FE-SEM and Raman spectrum revealed that it was mainly composed of single-walled CNT bundles with well alignment.

並列關鍵字

floating catalyst method ； single-walled carbon nanotube ； optimization ； long carbon nanotube strand

參考文獻

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