本研究探討軟性基板之碳微管微型化超高電容器製作，並分析承載氫氧化鈷和氧化釕的電容器電化學性質。微型化平面超高電容器兩極為指梳狀電極，指梳間隔20 μm，電容器電極圖型製作是經由黃光微影蝕刻、化學氣相沉積法和電化學沉積法。由於微型化超高電容器尺寸小和薄膜製程技術等優點，未來能輕易的與微機電系統做整合。
我們研究對稱式電容器 (CNT_CNT) 與非對稱式電容器 (CNT_ α-Co(OH)2/CNT或CNT_ RuO2•xH2O/CNT) 的電化學性質，經由循環伏安法和恆電流充放電測試，分析其比電容值、能量密度和功率密度等電化學性質，其中，更針對非對稱式電容器於放電過程中分析其個別電極之電容及電壓變化。
在電極製作上，我們能成功用電氣絕緣聚酯膠帶將指叉式碳微管陣列從矽基板移轉至軟性基板上。移轉前我們能先在碳微管圖型電極表面濺鍍一層金以利電流收集，再將電極反轉並移轉至膠帶上，此時，導電性佳的金面已在碳微管底部，並與每根碳微管在電性上有良好的電接觸，因此能有效降低電極阻抗、提升電容器之功率。
實驗結果顯示，移轉後之超高電容器其功率值遠大於從前本實驗室所製備的硬性電容器的表現。對稱式電容器 (CNT_CNT) 操作電壓1.8 V，電流密度30 Ag-1下能量密度和功率密度分別為2.2 Whkg-1、20.6 kWkg-1；非對稱式電容器 (CNT_α-Co(OH)2/CNT) 操作電壓1.8 V，電流密度35 Ag-1下能量密度和功率密度分別為5.9 Whkg-1、14.5 kWkg-1；非對稱式電容器 (CNT_ RuO2•xH2O/CNT) 操作電壓1.8 V，電流密度32 Ag-1下能量密度和功率密度分別為16.5 Whkg-1、16.2 kWkg-1，雖然釕材料價格上相較鈷貴上許多，但它在電性表現上還是相當具有優勢，非對稱式電容器 (CNT_ RuO2•xH2O /CNT) 更可操作在2 V的電壓下，有利於提高能量密度和功率密度，電流密度40 Ag-1下分別為24.0 Whkg-1、22.9 kWkg-1。
我們認為非對稱式電容器 (CNT_RuO2•xH2O/CNT) 的高能量密度，基於其複合式電極RuO2•xH2O/CNT之高比電容值，RuO2•xH2O /CNT的電容，相較α-Co(OH)2/CNT高出甚多。

We have investigated preparation and properties of the miniaturized ultracapacitors loaded with carbon nanotubes (CNT) , α-Co(OH)2, and RuO2˙xH2O on a flexible substrate. These ultracapacitors are featured with 20 μm–spaced comb-like electrodes, which are patterned using the standard technologies of photolithography, chemical vapor deposition, and electrodeposition. Owing to the mini size and the synthesis techniques, they can be easily integrated into portable electronics.
Correlation between the structure and energy storage property is studied with two ultracapacitors, a symmetric CNT_CNT capacitor and an asymmetric capacitor of CNT_α-Co(OH)2/CNT or CNT_RuO2•xH2O/CNT. The electrode capacitance of each electrode is measured with cyclic voltammetry (CV). Energy and power performance of symmetric and asymmetric capacitor are evaluated using galvanostatic charge-discharge experiment. If appropriate, the voltage and the capacitance of individual electrode of the working cell are analyzed during the cell discharge process.
On synthesis, a major achievement in this study is to demonstrate that the interdigital pattern of CNT electrode can be transferred from a rigid substrate to a flexible (polymeric) substrate using polyester tape. The transfer step allows us to pre-sputter a layer of gold on the top surface of CNT pattern electrode, after inversion and transfer, the gold-sputtered surface turns into a conductive bottom of CNT pattern. The conductive CNT bottom assures every nanotube is electrically connected to the current collector, reduces the electrode resistance significantly, and make possible a high-power cell.
Consequently, the power performance of these ultracapacitors is far better than that of the previous ultracapacitors synthesized in our research group. At a current density of 30 Ag-1 and a potential window 1.8 V, the CNT_CNT cell discharges at a power level 20.6 kWkg-1 with energy density 2.2 Wh kg-1. At a current density of 35 Ag-1 and a potential window of 1.8 V, the CNT_α-Co(OH)2/CNT cell discharges at a power level 14.5 kWkg-1 with energy density 5.9 Whkg-1. At current density of 32 Ag-1 and a potential window of 1.8 V, the CNT_RuO2•xH2O/CNT cell discharges at a power level 16.2 kWkg-1 with energy density 16.5 Whkg-1. Although ruthenium costs more than cobalt in material price, its asymmetric cell excels in both energy and power density. Furthermore, the CNT_RuO2•xH2/CNT cell can be operated at a potential window of 2.0 V, at current density of 40 Ag-1, it discharges at a power level 22.9 kWkg-1 with energy density 24.0 Whkg-1.
We attribute the higher energy density of CNT_RuO2•xH2O /CNT cell to the higher capacitance of its oxide electrode. The CV results indicate the capacitance of RuO2•xH2O/CNT is much higher than that of α-Co(OH)2 /CNT.

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