本研究使用停滯面油盤燃燒器產生擴散火焰合成奈米碳管。在上燃燒器中通入不同比例的氮氧混合氣體(氧濃度15%、17%、19%、21%)，下燃燒器中使用不同濃度的含水乙醇（燃料濃度80%、85%、90%、95%、99.5%）作爲燃料，探究火焰形態、溫度以及取樣位置對火焰合成奈米碳結構的影響。
實驗中首先對火焰形態進行觀察，並測量火焰溫度。停滯面油盤燃燒器會產生藍色平面火焰。隨着燃料濃度和氧氣濃度的降低，火焰強度發生變化，表現爲亮度減弱、高度下降、溫度降低。隨後，使用鎳網格對火焰面下方不同位置（△z = 0.5, 1.0, 1.5, 2.0 mm）進行取樣，取樣時間爲1分鐘，並且使用掃描式電子顯微鏡（SEM）、穿透式電子顯微鏡（TEM）對生成結果進行分析。
SEM結果顯示，當乙醇濃度爲99.5%，氧濃度爲19%時，△z = 1.0 mm處會大量捲曲的奈米碳管。如果固定氧濃度爲19%，降低乙醇濃度至95%，，△z = 1.0, 1.5 mm兩處有奈米碳管合成；繼續降低乙醇濃度至85%，，△z = 1.0, 1.5, 2.0 mm三處都會有奈米碳管合成。如果固定乙醇濃度爲99.5%,降低氧濃度至17%，△z = 1.0, 1.5 mm兩處有奈米碳管生長；降低氧濃度至15%，△z = 1.0, 1.5, 2.0 mm三處都會生長奈米碳管。降低燃料濃度和氧氣濃度，會使火焰溫度降低，奈米碳管的合成區間擴大，生長狀況變好。在低火焰溫度的環境下，乙醇分解產生的碳源(前驅物)，能與金屬觸媒產生更有效的反應，因而利於奈米碳管的生長。其適合奈米碳管合成的溫度範圍大約為425-1010 °C。
TEM觀察奈米碳管爲多壁奈米碳管（MWCNTs），且具有竹節狀結構。碳管的頂端和轉折處有顆粒物，可能爲催化金屬顆粒，顯示奈米碳管可能由頂端和底端生長機制合成。

The formation and growth of carbon nanotubes (CNTs) in aqueous ethanol diffusion flames by using a liquid pool burner were experimentally studied in this research. Oxygen/nitrogen mixture of different oxygen concentrations (15%, 17%, 19%, 21%) were passed into the upper burner, and the lower burner took different volumetric ethanol concentration (80%, 85%, 90%, 95%, 99.5%) of aqueous ethanol as fuel. The carbon nanotubes under the influence of flame structures, flame height, flame temperature, and sampling position were investigated.
The experiment started with an observation towards the shape of flame, and measuring of flame temperature. A blue flame without yellow soot layer arose on liquid pool burner. The results showed that lowering the concentration of oxygen and ethanol led to a decrease in the flame brightness, height and temperature. Nickel grids was served as the metal catalyst substrate to deposit carbon nanotubes at different sampling positions (0.5, 1.0, 1.5, 2.0 mm) below the flame surface, the sampling time was 1 minute. Additionally, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to observe and analyze the microstructure and morphology of generated carbon nanotubes under different experimental conditions.
The results of SEM analysis showed that numerous curved and entangled tubular CNTs were fabricated under 19% of oxygen concentration and 99.5% of ethanol concentration at 1.0 mm below the flame surface. By lowering the ethanol concentration down to 95%, CNTs were synthesized both at 1.0 and 1.5 mm below the flame surface; by further decreasing the ethanol concentration to 85%, CNTs were produced at 1.0, 1.5, and 2.0 mm below the flame surface. Similarly, lower oxygen concentration could also facilitate the growth of CNTs. It is noteworthy that lowering the concentration of oxygen and ethanol can reduce the flame temperature and provide suitable environments for the growth of carbon nanotubes. A temperature range from 425 to 1010 degrees were suitable for fabrication CNTs.
The TEM image showed that multi-walled (MWCNTs) were harvested, which had both typical straight and bamboo-like structures. Many catalysis metal particles were encapsulated in CNTs, which conformed the tip and base growth model of CNTs.

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