電化學電容器因電子產業發展迅速, 能源需求增加, 愈顯得其重要性. 本實驗以碳纖維為基板, 在碳纖維上成長奈米碳管, 碳纖維上濺鍍二氧化銥及將二氧化銥濺鍍在碳纖維上之奈米碳管做為電化學電容器電極材料. 因碳纖維具有柔軟, 導電性佳及與奈米碳管良好之結合性. 且奈米碳管與二氧化銥具有高導電性及高化學穩定性, 並可利用其大比表面積性質增加與電解質之接觸面積, 因此可有效提高電化學電容特性. 本實驗以KOH溶液為電解質, 並利用二極及三極量測法量測其電化學電容特性, 其中以二極量測法測得碳纖維, 碳纖維上成長奈米碳管, 碳纖維上濺鍍二氧化銥及濺鍍二氧化銥於碳纖維上之奈米碳管電容值, 分別為 7.00×10-3, 6.94, 34.54及32.85 Fg-1, 若以三極量測法量測, 則可分別得到1.01×10-2, 35.71, 123.46及153.05 Fg-1電容值. 其中二氧化銥濺鍍於碳纖維基板及二氧化銥濺鍍在碳纖維上之奈米碳管電極材料, 其電容值表現較佳. 在電容充放電實驗中, 經過100次充放電後, 亦可保持穩定之電化學電容特性. 本實驗結果指出二氧化銥濺鍍於碳纖維基板及二氧化銥濺鍍在碳纖維上之奈米碳管皆為良好之電化學電極材料.

Electrochemical capacitors become more important because of rapid development of the electronic product and the increasing of the energy demand. In this study, we probed the electrochemical characteristics for carbon fibers, (carbon nanotubes, CNTs)/carbon fibers, IrO2/carbon fibers, and IrO2/CNTs/carbon fibers. Due to the advantages of carbon fibers such as flexure, curled surface, good electric properties, and easy-contact with carbon, carbon fibers were used as the substrate. CNTs and IrO2 presented high conductivity, chemical stability, and large surface area which increase the interactive area with electrolyte to enhance the capacitance of electrochemical capacitor. The supporting electrolyte was KOH solution. The measurements of electrochemical capacitor were 2-electrode system and
3-electrode system. The specific capacitance values of carbon fiber, CNTs/carbon fibers, IrO2/carbon fibers and IrO2/CNTs/carbon fibers electrodes were 7.00×10-3, 6.94, 34.54, 32.85 Fg-1 in 2-electrode system, and 1.01×10-2, 35.71, 123.46, 153.05 Fg-1 in 3-electrode system, respectively. The electrochemical measurements showed that the IrO2/carbon fibers and IrO2/CNTs/carbon fibers had good performances of electrochemical capacitors. We measured the electrodes by charge-discharge 100 cycles and found that they maintained electrochemical characteristics. The results indicate that the IrO2/carbon fibers and IrO2/CNTs/carbon fibers are excellent electrochemical electrodes.

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