本研究中以高比表面積與良好導電性的石墨烯碳材作為載體，並負載氧化鉬顆粒來增加催化釩離子反應的活性。利用水熱法及化學氣相沉積儀製備出氧化鉬奈米顆粒，再以迴流法與高溫燒結將氧化鉬顆粒嵌入石墨烯中，形成複合物觸媒。藉由結構與性質分析來了解此複合物觸媒的特性，利用XRD確認複合物由二氧化鉬與還原氧化石墨烯所組成。在拉曼光譜分析的結果，可得知複合物中石墨烯碳材與二氧化鉬的結構缺陷增加，而在FT-IR與XPS分析中可確認複合物樣品含有大量的氧官能基。氧官能基為催化釩離子氧化還原反應的電化學活性點位，在電化學量測中可確認利用此方法合成的複合物觸媒具有良好的電子傳導性質，可歸因於還原氧化石墨烯的優良導電性。將此複合物觸媒應用於碳氈電極改質，以改質後的碳氈進行充、放電測試，其電極效能在40 mA/cm2與80 mA/cm2的充、放電電流密度下，分別表現出80.37%及77.39%的能量效率。相較於熱處理的碳氈，以此複合物觸媒改質的電極效能表現更優異的電催化效果。

In this study, use the high specific surface area and good conductivity graphene material as a carrier, and load molybdenum oxide particles to enhance the catalytic activity to vanadium ion reaction. Molybdenum oxide nanoparticles are prepared by hydrothermal method and chemical vapor deposition system, and then molybdenum oxide particles are embedded in graphene by reflux method and high temperature sintering, to form a composite catalyst. Observe the characteristics of this composite catalyst through structure and property analysis, use XRD to confirm that the composite was composed of molybdenum dioxide and reduced graphene oxide. In the Raman spectroscopy analysis, it can confirm that the defect in graphene structure and molybdenum dioxide was increase in the composite, and it can know that the composite sample contains a large amount of oxygen functional groups by FT-IR and XPS analysis. Oxygen functional groups are electrochemical active sites for the vanadium ions redox reaction. In the electrochemical measurement, it can be confirmed that the composite catalyst synthesized by this method has good electronic conductivity properties, this can ascribe to the good conductivity of the reduced graphene oxide, the composite catalyst was applied to the modification of carbon felt electrodes, and the modified carbon felt was used for charging and discharging tests. The electrode modified by this composite exhibits the energy efficiency of 80.37% and 77.39% at the current densities of 40 mA/cm2 and 80 mA/cm2., compared with the heat-treated carbon felt, the electrode performance modified by the composite catalyst has better electrochemical performance.

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