石墨烯因為它所具備獨特的電子遷移率和機械強度之優異表現，引起廣泛的興趣和深入的探討。除了能顯著提高電子元件的性能，還在新材料和工業應用中展現出無法忽視的潛力。近年來研究人員致力於開發各種高效能的石墨烯製造技術，其中以化學氣相沉積法和還原氧化石墨烯這兩種方法在表現出大規模生產的顯著優勢。本研究將進一步討論使用電漿及熱裂解甲烷後，所製造出的石墨烯材料物性。
本研究中，以五種方法製作出來的的材料，首先使用X光繞射法去計算產物之有序晶格長度。並使用拉曼光譜來分析碳-碳間單鍵、雙鍵的比例。從拉曼光譜中可以觀察到每個產物均有G和D之特徵峰，但其相對強度不同。而各產物之間的2D峰強度差異則更加明顯。這個結果顯示出Cyclone跟Tube與石墨烯具有較為相似之圖譜。透過X光光電子能譜的量測結果，可以分析出產物中的元素，並計算出C-C和C=C鍵結的比值。比表面積及孔徑分析儀則可告訴我們各材料的孔徑大小，與對氮氣的吸、脫附能力。本研究也透過電化學阻抗譜，觀察各產物在直流與交流電下的電阻變化。

Graphene has attracted significant attention and in-depth investigation due to its exceptional electronic mobility and outstanding mechanical strength. Beyond its potential to significantly enhance the performance of electronic devices, graphene has also shown immense promise in the development of novel materials and industrial applications. In recent years, researchers have devoted considerable effort to developing efficient production techniques for graphene. Among these, chemical vapor deposition (CVD) and the reduction of graphene oxide have emerged as up-and-coming methods for large-scale synthesis. This study further investigates the physical properties of graphene-based materials synthesized through the plasma and thermal pyrolysis of methane.
In this research, five different synthesis methods were employed to produce graphene-related materials. X-ray diffraction (XRD) was first utilized to evaluate the degree of crystallinity and estimate the lattice coherence length of the synthesized products. Raman spectroscopy was then applied to analyze the relative proportions of sp² (C=C) and sp³ (C–C) hybridized carbon bonds. The Raman spectra for all samples exhibit characteristic G and D bands, though their relative intensities vary across samples. Notably, significant differences were observed in the 2D band intensity, with the spectra of the Cyclone and Tube samples closely resembling that of ideal graphene.
X-ray photoelectron spectroscopy (XPS) was conducted to identify the elemental composition of the samples and to quantify the ratio of C–C to C=C bonds. Brunauer–Emmett–Teller (BET) surface area analysis and pore size distribution measurements were also performed to determine the porosity and gas adsorption/desorption capabilities of the materials. Finally, electrochemical impedance spectroscopy (EIS) was used to investigate the variation in electrical resistance of the samples under both direct current (DC) and alternating current (AC) conditions.
These comprehensive characterizations provide insights into the structural, chemical, and electrochemical properties of the synthesized graphene materials, thereby contributing to the development of high-performance graphene-based technologies.

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