本研究主要在使用高溫水熱法合成含有還原氧化石墨烯和金屬奈米複合材料與二氧化鈦，經由退火改善原本二氧化鈦奈米複合材料的特性，以應用在超級電容之製作。首先將不同反應後的材料進行微拉曼光譜，Ｘ光繞射，Ｘ-ray光電子光譜和掃描式電子顯微鏡分析，了解反應後材料的結構與生成的產物，接著，再藉由化學循環伏安法和充放電等，探討整個超級電容的特性。
為了提升電極材料的導電度，選擇將銀加入其中，以改善二氧化鈦的導電性，其超級電容值提升了2.5倍；接著，選擇添加具有相當高表面積對質量比例(2000~3000 cm/g)特性的還原氧化石墨烯，提升了超級電容值約為三倍的特性；最後，選擇添加過渡金屬元素釕，因為釕本身擁有許多氧化態（2價，3價，4價，6價和8價），使得電荷儲存不僅僅只有電雙層電容的電荷，也包含偽電容電荷的儲存，因此整個超級電容值更提升了近4倍。

In this thesis, TiO2 nanocomposites with the incorporation of different nano-structured metals and reduced graphene oxide were synthesized by hydrothermal for supercapacitor applications. The synthesized TiO2 nanocomposites were annealed and then characterized by Microscopes Raman Spectrometer, X-Ray Diffractometer, X-ray Photoelectron Spectroscopy, and Field Emission Scanning Electron Microscopy to indentify the structures and compositions. Then, the characteristics of the supercapacitors were investigated through cyclic voltammetry, and galvanostatic current charge–discharge.
Silver is considered to be a good conductor for its high conductivity to improve the electrochemical property of TiO2. The incorporation of Ag in TiO2 for supercapacitor enhances the specific capacitance about 2.5 times as compared to that of TiO2. After reaction with the high surface area/mass ratio (2000~3000 cm/g) of reduced graphene oxide, the specific capacitance is 3 times larger than the pure TiO2 material. Ru, filled with a lot of oxidation states (2, 3, 4, 6 and 8), was incorporated in TiO2. The electrical charges are stored not only by electrical double layer capacitive mechanism but also through pseudo-capacitive mechanism. Therefore, the specific capacitance of the nanocomposites can be further improved by 4 times as compared to that of the pure TiO2 material.

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