奈米碳管與金屬氧化物之電漿處理與光譜研究

Plasma treatment and spectroscopic studies on carbon nanotubes and metal oxides

彭志偉(Jr-Wei Peng)

指導教授 ： 李世琛

中原大學/理學院/化學研究所/博士(2011年)

https://doi.org/10.6840/cycu201100687

摘要

本論文共分成三個部份，第一部份為利用氬氣混合水蒸氣所產生的常壓羥基電漿處理多壁奈米碳管。我們藉由拉曼光譜中的D、G、D’和G’ bands的強度比值、位置和線寬的色散行為觀察電漿對多壁奈米碳管所造成的缺陷和氧化過程。我們採用簡單的動力學反應模型解釋多壁奈米碳管經電漿處理後所產生的拉曼色散趨勢，同時也利用X射線光電子光譜更進一步證實拉曼光譜之分析結果。第二部份為利用硫酸和硝酸之混合溶液對多壁奈米碳管進行氧化處理。我們藉由掃描式電子顯微鏡量測多壁奈米碳管之直徑分佈的變化。我們發現拉曼光譜中，D和G之強度比值的色散行為與直徑分佈有關，並證實曲率效應可增強度比值之色散行為。而碳管氧化過程中所造成的缺陷會使譜帶位置產生位移。第三部份中，我們先以低壓氫電漿處理氧化鋅、氧化銅及二氧化錫，並由漫反射光譜中發現，氫電漿造成氧化鋅和氧化銅的能隙藍位移，二氧化錫的能隙則是紅位移。我們再以低壓氧電漿處理氧化鋅、氧化銅及二氧化錫後，此三種金屬氧化物的能隙皆能還原至原來的能隙。同時，我們利用放光光譜、光激螢光光譜、X光繞射光譜等光譜量測技術說明造成氧化鋅、氧化銅及二氧化錫的能隙變化的原因。

關鍵字

拉曼 ； 奈米碳管 ； 電漿 ； 金屬氧化物

並列摘要

The thesis contains three parts. In the first part, multi-walled carbon nanotubes (MWCNTs) were treated with an atmospheric pressure hydroxyl radical plasma. We use Raman dispersion of the intensity ratio, band position and linewidth of the D, G, D’, and G’ bands to probe the defect fornation and oxidation process in MWCNTs. The X-ray photoelectron spectroscopy confirmed the Raman dispersion behavior.In the second part, MWCNTs were chemically oxided with a solution. The diameter distribution variation in MWCNTs has been measured by scanning electron microscopy. The Raman dispersion behaviors of the intensity ratio of the D and G band were correlated with the MWCNTs diameter distribution. Curvature effect has been proved to be important in enhancing the Raman dispersion effects. On the other hand, defect formation dominates the band position trend.In the third part, zinc oxide, copper oxide and tin dioxide were treated with a low pressure H plasma first and monitored by diffused reflectance spectra. H plasma caused the blue shift of the band gap values of zinc oxide and cooper oxide. On the other hand, red shift of the band gap values of tin dioxide was observed. Then these metal oxides were treated by O plasma, the band gap of these metal oxides shifted back close to initial value. We used optical emission, photolumiscence, and X-ray diffraction spectra to explain the band gap shifting behaviors of these metal oxides.

並列關鍵字

plasma ； carbon nanotube ； metal oxide ； raman

參考文獻

66. 許嘉緯, “碲化鋅半導體量子點之光學特性研究", 中原大學應用物理研究所 (2003).

1. S. Iijima, ” Helical mictotubules of graphitic carbon”, Nature, 354, 56-58 (1991).

2. R. Saito, G. Dresselhaus and M. S. Dresselhaus, “Physical of properties of carbon nanotubes”, Imperial College Press (1999).

3. D. Luxembourg, G. Flamant, E. Beche, J.-L. Sans, J. Giral and V. Goetz, “Hydrogen storage capacity at high pressure of raw and purified single wall carbon nanotubes produced with a solar reactor “, Int. J. Hydrogen Energy, 32, 1016-1023 (2007).

4. C. Liu, Y. Y. Fan, M. Liu, H. T. Cong, H. M. Cheng and M. S. Dresselhaus, ” Hydrogen storage in single-walled carbon nanotubes at room temperature”, Science 286, 1127-1129 (1999).