本研究使用易於製備的循環伏安法沉積二氧化釕(RuO2)薄膜在垂直成長的石墨烯纖維(Graphene nanofiber)上，並應用在電化學電容。此奈米結構的複合材料經由高解析度的穿透視電子顯微鏡可觀查到二氧化釕奈米顆粒均穩定附著在石墨烯纖維上；拉曼光譜儀則檢驗二氧化釕-石墨烯纖維的分子鍵結；而其化學鍵結狀態則由X射線光電子能譜分析。在電性分析方面，則是使用循環伏安法、恆電流充放電測試及電化學阻抗頻譜。從上述分析中可得知我們製備的複合材料比單純二氧化釕薄膜提昇了3.5倍的比電容值，而該電極材料的比電容值為53.7 mF cm-2。另外從電化學阻抗頻譜分析發現二氧化釕-石墨烯纖維的材料呈現良好的導電性。這些結果證明了我們所合成的電極材料是一個極具潛力的超級電容應用，對於未來儲能元件的發展佔有一席重要之地。

In this work, ruthenium oxide (RuO2¬) thin films were synthesized onto the surface of the vertically grown graphene nanofibers (GNFs) by cyclic voltammetric (CV) deposition, an easy and efficient solution-based method, have been investigated for potential application in electrochemical capacitors (ECs). The nanostructure of RuO2/GNF was characterized by the high-resolution transmission electron microscopy (HRTEM). From the HRTEM image, the RuO2 nanoparticles were anchored onto the GNFs. The Raman spectrum was used to examine the characteristic of the RuO2/GNF. The chemical states and characteristic of RuO2/GNF were confirmed by the X-ray photoelectron spectroscopy (XPS). The electrochemical properties were characterized by cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance spectra (EIS). From studying the electrochemical charge storage properties of RuO2/GNF, electrochemical measurements reveal that the maximum specific capacitance of the RuO2/GNF electrodes is 53.7 mF cm-2. This is attributed to RuO2 is well-dispersed on GNFs.

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