本實驗利用射頻磁控濺鍍法於低溫下成長具半導體特性之非晶質奈米碳棒，其形貌不同於一般使用濺鍍法成長之薄膜。本實驗從兩方面來對成長奈米碳棒做探討，首先，我們於不同溫度下成長奈米碳棒，並觀察其表面形貌及結構隨著成長溫度的改變之變化，實驗結果顯示，奈米碳棒具有粗糙樹枝狀的表面形貌且為實心的棒狀結構，其表面形貌並不隨著成長溫度的提高而有所改變，而其結晶性會隨著成長溫度的提高而變好，但其結構仍存在許多無序的鍵結。另一方面，我們將並藉由調控成長過程中通入氬氣及氮氣之比例，來控制氮摻雜含量，在實驗中，我們發現奈米碳棒調控通入氬氣及氮氣的比例能決定成長出碳膜亦或垂直奈米碳棒。當通入之氣體為氬氣及氮氣之混合氣時，由於解離之氬離子及氮離子的大小、質量及能量都不同，因此從碳靶材轟擊出大小、質量及能量不均之碳粒子吸附在基板上進而形成核島，後續吸附上之碳粒子接著向核島聚集以降低表面能然後繼而成長為奈米碳棒，且由於此奈米碳棒是由大小粒徑不一的碳粒子建構而成，因此形成粗糙的表面現象且擁有極高的比表面積。反之，當通入之氣體為純氬氣或氮氣時，則成長出碳膜。此外，我們將不同氮摻雜含量之奈米碳棒應用於燃料電池之陰極觸媒，在鹼性的環境中藉由旋轉環盤電極測量其氧氣還原活性，隨著氮摻雜含量上升，電流密度隨之增大，當氮含量為31.87 at.%其陰極氧氣還原電流密度可達-7.8 mA/cm2，啟動電位為-0.2 V (vs. Ag/AgCl)，電子轉移
數為3.92，過氧化氫的產率為1.80%。而藉由X射線光電子能譜儀分析氮摻雜奈米碳棒得知pyridinic–N的含量隨著氮含量的增加而增加，證明了pyridinic–N與奈米碳棒的氧氣還原活性有直接的關係。因此本實驗除了證明本實驗成長之奈米碳棒可達到高氮摻雜含量之外，其對於氧氣還原具有高活性及高選擇性，為具有潛力的燃料電池非貴重金屬陰極觸媒。另外，本論文亦將奈米碳棒成長於石墨烯上，利用具有高比表面積的一維奈米碳棒與二維的石墨烯做結合，製造出三維的複合材料並應用於電雙層電容之電極。其優點為：(1)在接面結構上為碳-碳鍵結，可以有效降低接面阻抗，(2)增加電子在元件中的傳輸速度。在此實驗中，我們利用三極量測法量測電極的電容特性，並將電極分別置於30℃、40℃、50℃及60℃的鹼性環境中以測試其在高溫的環境仍具有良好的穩定性。實驗結果顯示，隨著量測環境的溫度升高其比電容值也隨之變大，進行1000圈充放電測試後其比電容值於30℃、40℃、50℃及60℃的環境中依序為405、520、670及830 F/g，證明了本實驗成長之奈米碳棒為擁有極佳的比電容值及具有良好穩定性之電極材料。

We present a method for growing carbon nano rods (CNR), an allotrope of 1-D carbon, using radio frequency magnetron sputtering at low temperature. We first investigate how the growth temperature (from room temperature to 380℃) and sputtering gas (Ar and N2) influence the CNR morphology and structure. The resulting CNRs were observed to be aligned vertically onto the substrate with uniform length exhibiting an amorphous structure with semiconducting properties. The CNR morphology did not change obviously but the crystallinity was enhanced with an increase in the growth temperature. Moreover, different CNR morphologies were observed when synthesized using various Ar/N2 sputtering gas ratios. Film-like CNRs were formed when pure N2 (or Ar) was used as the sputtering gas. Rod-like CNRs were formed when mixed Ar and N2 sputtering gas was applied. These inconsistent results indicate that sputtered carbon particles of different sizes and energy can be ascribed to the CNR formation. CNRs doped with different nitrogen content was used as the cathode catalysts for the proton exchange membrane fuel cell (PEMFC). The catalytic activity toward the oxygen reduction reaction (ORR) was studied. The nitrogen content was controlled directly by adjusting the Ar/N2 ratio during CNR growth. The nitrogen content and C–N bonding configuration of the samples were characterized using X-ray photoelectron spectroscopy, which demonstrated that the nitrogen content can reach up to 31.87% and the pyridinic-type nitrogen content increased with the increase in nitrogen content. The nitrogen-doped CNR with the largest amount of pyridinic-type nitrogen configuration exhibits superior ORR activity, which leads to a four-electron transfer in alkaline solution. The reduction current density can reach up to -7.8 mA/cm2, which opens the possibility for metal-free PEMFC catalysts applications. On the other hand, a hybrid 3-D structure, CNRs/graphene, was fabricated by combining highly conductive graphene (2-D) with vertically aligned CNRs (1-D). We used CNRs as the electrode and graphene as the current collector for electric double layer capacitor (EDLC) applications. The CNR and graphene combination has the following advantages: (1) The C–C bonding of the interface can effectively lower the impedance; (2) The structure can enhance the electron transmission speed in the device. The synthesized CNRs on graphene presented high number density, high direct aspect and large surface area, which can increase the reactive surface area between the electrode and electrolyte. The capacitor performance was characterized using cyclic voltammetry and galvanostatic charge-discharge testing in 1 M KOH electrolyte at 30℃, 40℃, 50℃, and 60℃. The CNR specific capacitance was observed to increase with increasing measurement temperature and could reach up to 830 F/g at 60℃. Even after extensive measurements, the CNR electrode maintained good adhesion to the graphene current collector, thereby suggesting electrode material stability.

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