石墨烯與氧化石墨烯的製備與鑑定

Preparation and Characterization of Graphene and Graphene Oxide

韋峻文(Chun Wen Wei)

指導教授 ： 洪偉修

國立臺灣師範大學/理學院/化學系/碩士(2011年)

摘要

第一部分：
我們利用X光光電子能譜與粉末X光繞射光譜觀察石墨材料在氧化製程中的變化，過錳酸鉀會破壞石墨結晶中的雙鍵而產生含氧的官能基，當使用超聲波震盪時，含氧官能基彼此會產生靜電斥力，而達到石墨結構層與層之間的分離。從XPS圖譜可以看出，碳的訊號會因為氧化造成導電度下降而往高能量飄移，氧化所造成的官能基變化也可以從碳的XPS圖譜得知。根據文獻，碳的訊號會由碳材料及3種鍵結在碳材料上的含氧官能基所貢獻，分別有不同的能量。而X光粉末繞射圖譜也可發現石墨(002)晶面的訊號會隨氧化時間而往低角度飄移。分析以上兩種光譜，我們可以知道碳材料的結構變化與氧化程度。
由上述實驗所得到的結果，我們結合氧化時間為6小時、超聲波震盪1小時的兩道製程條件製備氧化石墨烯。並利用原子力顯微鏡等儀器做鑑定，證明我們所設計的製程條件可以製備出低層數、分散均勻(在水中)的氧化石墨烯。

第二部分:
我們進一步以有機修飾或是還原劑還原的方式改變氧化石墨烯的特性，並以儀器做鑑定。從各種鑑定結果我們發現，石墨烯氧化物的特性會因為官能基改變或是還原後而有不同的性質。

關鍵字

石墨 ； 石墨烯 ； 氧化石墨烯 ； 碳複合材料

並列摘要

Section 1:
We studied the changes of graphite in the chemical oxidation process by XPS and XRD spectroscopy. The oxidant (KMnO4) will destroy the double bonds in the crystal structure of graphite to form oxygen containing functional groups. The chemical oxidation of graphite produced hydrophilic graphite oxide, which can be readily exfoliated as single layer graphene oxide sheet by ultrasonication in water. The result suggests that the formation of stable graphene oxide (GO) sheets should be attributed to electrostatic repulsion caused by oxygen containing groups. As shown in the XPS spectra, the C (1s) signal were high binding energy shifted that low electronic conductivity due to chemical oxidation to form an insulator. The change of functional groups caused by oxidation can be detected by XPS.
Based on the reported conclusion, C (1s) XPS spectra of GO materials clearly indicates a considerable degree of oxidation with four components that correspond to carbon atoms in different functional groups. The XRD spectra show that graphite (002) signal will change with increase of oxidation time and shift to low diffraction degree. According to the results of XPS and XRD, the changes of structure or degree of oxidation information will be available.
Based on the result of graphite oxidation process, we used 6 hour as reaction condition for graphene oxide production, and characterized by AFM, XPS, DLS, etc. These data suggest that the combined two-step process could be advantageous for production of GO.

Section 2:
The as-obtained GO were further modification and reduction to change the properties of GO, and characterized by AFM, DLS, FE-SEM, Raman, FT-IR, XRD, XPS, UV-vis. Those data show that the properties of GO will be changed by chemical reduction or functional modification.

並列關鍵字

Graphite ； Graphene ； Graphene oxide ； Carbon composite material

參考文獻

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