本論文主要是藉由有機金屬化學氣相沉積法製備具有不同二氧化釕奈米相電極，再利用SEM與XRD圖譜來分析奈米材料的結構特性，進而研究其循環伏安圖、充放電行為與交流阻抗的電化學電容性質。
利用MOCVD的方式，可於LiNbO3（100）與Sapphire（0001）兩種不同基材上合成出奈米桿與形似壁磚直立狀的二氧化釕材料，或控制沉積時間的長短，成長出具有不同高度的奈米桿。在LiNbO3基材上所成長出的二氧化釕奈米桿，成長方向[001]，繞射面（002）強度隨奈米桿高度增加而增強，且審視電鏡影像，隨著桿高的增加其奈米桿頂的尺寸也隨之增大，而當成長時間拉長時，觀察到的奈米桿數目密度隨之減少。在SA（0001）基材上的二氧化釕， RuO2[001]則貼著基材方向成長，且沿三個可能的基材方向SA[ ]發展。
RuO2/LNO與RuO2/SA兩不同形貌電極的循環伏安圖，經過長時間的電極作用後，在圖中的單晶特徵峰會漸漸地減少，而趨向似矩形。由可收授電容值圖形可了解到，掃流速率增加時因受內電阻影響亦增加，導致在電極的可收授電容值有隨之降低的驅勢，且當掃流速率增大到700mV/sec以上，其奈米桿單位面積上的電荷量與掃流速率平方根的關係有偏離原本線性的現象，但奈米磚則不致如此，這顯示奈米桿電極雖擁有的比面積比形似壁磚直立狀的電極高，但在高掃流速率下並非全部面積都有真正貢獻到。而因二氧化釕材料於電極底部跟表面部分的孔隙度有所差別，使得在充放電的圖形中我們可發現有高低充放電速率區的不同。
我們製備的奈米桿電極，其電容值隨著奈米桿高度增加而增加，說明了因奈米桿高度增加所帶來高表面積的效應，但也因孔隙深度的增加，讓孔洞內面積無法像孔洞口面積一般等效貢獻於電容。由不同高度二氧化釕奈米桿充放電行為所測得的的比能量會隨著高度的增高而變大，這與所測得的比電容量有相同的趨勢，但其比功率卻是隨高度增加而變小，可由內部電阻增加解釋之，交流阻抗分析圖譜亦指出內部電阻隨奈米桿高度增加而增加，而且顯示較矮的奈米桿電容功率應較大。一般而論，與其它電容相比較，RuO2奈米桿的電容比功率是相當高的。放在Ragone圖中與其他超高電容與電池比較，RuO2奈米桿電容具有超高電容的比功率與二次電池的比能量。

The thesis discusses the preparation of RuO2 nanophases with various structural feature, and the characterization them using scanning electron microscopy SEM and X-ray diffraction XRD. The RuO2 nanophase electrodes are used in fabricating the electrochemical capacitors. Their capacitative properties are studied using cyclic voltammetry CV, charging-discharging measurement, and electrochemical impedance spectroscopy EIS.
Through metalorganic chemical vapor deposition, RuO2 nanophases of standing rods and tiles are grown on LiNbO3(100) LNO and sapphire(0001) SA substrates. We have also grown nanorods of different height via control on the deposition time. The nanorods are vertically grown on LiNbO3(100) in the [001] direction of rutile structure. The intensity of the reflection plane (002) increases with the average height of nanorods. Inspection of the SEM images shows that the number density of nanorods decreases as the deposition time increases. The growth direction [001] of the nanophase on SA(0001) is along the substrate plane. The growth direction is along one of the three possible SA[ 010] directions.
Comparison of the CV diagrams of two nanophases on LNO and SA substrates indicates that the characteristic peaks of RuO2 single crystals decrease after prolonged cycling, and the diagrams approach a mirror-like rectangle. The diagram of accessible charge versus electrode potential shows that the influence of internal resistance increases with the sweep rate, and it leads to reduction of accessible charge. When the sweep rate is over 700 mVs-1, the accessible charge of nanorods deviates from the linear relation with the square root of sweep rate, but not that of nanometer tiles. The CV results suggest that although the capacitance of nanorods is higher, yet not the entire electrolyte-solid interface contribute to the capacitance under high sweep rate. Also owing to the difference between the nanophases near the substrate and those away from the substrate, the charge rate can be distinguished into the fast and the slow charging regions, so is the discharging rate.
The nanorods capacitors prepared exhibit the capacitance increases with the average height of rods. The capacitance increase points out the effect of increasing surface area. But the inner area of nanorods is not as effective as the outer surface in contribution in capacitance increase because the depth also increases. The charge-discharge measurement of different height nanorods indicates that the specific energy stored increases with height, but the specific power decreases. The trend can also be explained by the internal resistance. The EIS spectra show that the internal resistance increases with the average height, and the shorter nanorods should possess higher specific power. Generally speaking, the specific power of RuO2 nanorods is relatively high. If the nanorods capacitors are placed in the Ragone plot and compared with other batteries and supercapacitors, the RuO2 nanorods capacitors are featured with the specific power of supercapacitors and the specific energy of secondary batteries.

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