具有分支結構的奈米碳管之製備、檢測、機制與應用

Production, Examination, Mechanisms and Applications of Branched Carbon Nanotubes

邱沛瑋(PEI-WEI CHIU)

指導教授 ： 陳建忠

國立中正大學/工學院/化學工程學系/碩士(2016年)

摘要

本論文是利用化學氣相沉積法在原始碳管上製備具有分支結構的奈米碳管，探討不同參數對於分支生長與主幹變化的影響，藉以合成不同型態的奈米碳管。
實驗是先將原始碳管進行純化處理，接著使用微濕含浸法將硝酸鎳水溶液含浸至純化奈米碳管，再由化學氣相沉積法以乙炔作為碳源，生長具有分支結構的奈米碳管。以還原溫度為450°C、反應溫度600°C、乙炔流量介於10~20 sccm且在反應過程中通入100 sccm氬氣的條件下，可合成主幹管徑約28~33nm且分支管徑約8~10 nm的細長分支碳管，之後藉由降低反應溫度至560°C、乙炔流量為10 sccm，可製備長度約33nm短小的分支，而使用管徑大的碳管為主幹時，反應後較容易得到密集且均勻分布的分支。
接著是將原始碳管和分支奈米碳管進行應用，將不具有導電性的PDMS與CNT混合，製備導電矽橡膠，另一方面是將CNT先做成CNT paper再以PDMS進行包覆形成複合材料，使用有分支的奈米碳管製備的複合材料，在電性方面皆有所提升，電阻值分別由43.47Ω和18.05Ω降至27.54 Ω和10.63 Ω，在複合材料兩端施加電壓，材料表面溫度會隨時間而上升，使其可作為可撓式電熱材料。

關鍵字

奈米碳管 ； 鎳奈米粒子 ； 分支奈米碳管 ； 導電矽橡膠

並列摘要

This thesis employs the method of chemical vapor deposition to produce branched nanotubes. A study of different parameters that affect the growth of branches and primary CNTs is investigated to synthesize various types of CNTs.
The experiment first deals with the purification of pristine carbon nanotubes. Next, we apply the method of incipient wetness to impregnate nickel nitrate solution on purified CNTs. Using acetylene as carbon source, the method of chemical vapor deposition is adopted to grow branched nanotubes. The reduction temperature and reaction temperature of this work are set to be 450 and 600°C, respectively. The acetylene flow is between 10 and 20 sccm. With argon flow of 100 sccm, primary CNTs of diameter 28~33nm and branch carbon tube of diameter 8~10nm can be successfully synthesized. Smaller branch nanotubes can be produced by lowering the reaction temperature to 560°C and maintaining acetylene flow as 10 sccm. temperature to 560°C and maintaining acetylene flow as 10 sccm. It is easier to obtain denser and more evenly distributed branches when larger carbon tubes are selected as primary CNTs.
Furthermore, the pristine and branched carbon nanotubes are mixed with non-conductive PDMS to produce conductive silicone rubber for application purposes. On the other hand, the CNTs are made into CNT paper and then wrapped with PDMS to form a compound material. Utilizing branched CNTs to produce the compound material and silicone rubber, the conductivity improves for both cases. The resistance values decrease from 43.47Ω and 18.05Ω to 27.54Ω and 10.63Ω, respectively. The surface temperature rises as an electric potential difference is applied between the two ends of the PDMS/CNT compound, making it a flexible thermoelectric material.

並列關鍵字

carbon nanotube ； Ni nanoparticles ； branched carbon nanotube ； conductive silicone rubber

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