本實驗以矽基板做為基底在上方成長奈米碳管束陣列，並以奈米碳管束陣列為模板披覆二氧化鈦做為電化學電容器的電極材料。奈米碳管有高導電性、高化學穩定性與高比表面積之特性，利用氣相沉積法成長奈米碳管束陣列之前先以網格布遮蔽基板，以簡單與低成本的方式定義柱狀陣列圖形樣式以增加電化學電雙層電容實驗中電介質電解液與電極的接觸面積。二氧化鈦有良好的偽電容特性，藉由氧化還原與可逆的法拉第電荷轉移可有效提升電雙層電容特性。溫度對於電化學電容器的電極有顯著的影響，會影響二氧化鈦的結構缺陷、應力或是結晶性等特性，常見的方式有後退火與控制電極的材料成長溫度。本實驗分別以後退火與控制電極的材料成長溫度製備二氧化鈦，由實驗結果得知控制二氧化鈦成長溫度的製程有較高的電容值。二氧化鈦/奈米碳管由循環伏安量測法可在成長溫度350℃得到最佳電容值723.8F/g。與奈米碳管電極的電容值0.5 F/g做比較，披覆二氧化鈦後的電極電容值成長倍率可達1447倍，是良好的電化學電極材料。

Vertically aligned carbon nanotube (CNT) arrays were grown on the silicon wafer, which was used as a template for TiO2 nanostructure growth. The nanostructure was used as a material for building an electrochemical capacitor. CNTs have many special properties such as chemical stability, good conductivity and high aspect ratio. By synthesizing the silicon wafer with mesh before growing the CNTs, the CNTs pattern can be designed to improve the electrolyte contact area of electrode. TiO2 exhibited extremely good pseudo-capacitor characteristics for redox reactions and reversible Faraday reaction. CNTs coated with TiO2 could be used to effectively enhance the electrochemical capacitor characteristic. The process temperature has significant effects on electrode formation. It affects the structural defects, stress, crystallinity of TiO2. We prepared TiO2 by controlling the growth temperatures and the post annealing in a vacuum environment. Using electric double-layer capacitor measurement, the capacitance could reach as high as 723.8 F/g with TiO2 growth temperature of 350℃. From the experimental results, the TiO2/CNT maintained stable electrochemical characteristics. The synthesized TiO2/CNT was suitable for the electrochemical applications.

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