在儲能裝置迅速發展下，超級電容器逐漸定位能夠支持快速充放電的高功率密度元件，其中又以電雙層電容器 (Electrostatic double-layer capacitor, EDLC) 更加適合操作於高功率密度下。因此，在本研究中將針對活性碳電極與電解質的介面進行優化，藉此改善離子移動的瓶頸，進一步提升EDLC在高功率密度下的性能表現。
首先，透過改良漢默法合成氧化石墨烯 (Graphene oxide, GO)，並將其作為活性碳電極的添加劑。在電極性質分析中，隨著電極中屬於不良導體的GO比例的上升，電極導電度隨之下降，然而GO表面的氧化官能基團促進了電極介面上鹽類的解離，自由離子的比例隨著GO比例提升而上升。接著組成對稱式超級電容器進行電化學性能測試。在超級電容器阻抗與比電容值等重要性能參數上，隨GO比例上升皆呈現先優化後劣化的趨勢，並且在GO添加比例為5 wt%時為最佳點，說明其在代表離子移動能力的自由離子比例與電極導電度上取得了折衷。而由於這個優勢，使得其在高功率密度的條件下擁有更好的性能，其能量密度上升了約31%。由於GO的添加僅改善了電極與電解質之間介面的離子移動能力，並且隨之而來的是抑制電子的導電度。因此將透過兩性離子的吸附，在不降低電極導電度的條件下，進一步提升離子於介面處以及活性碳孔洞內部的離子移動能力。將兩性離子 ([2-(Methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide, SBMA) 吸附於含有5 wt% GO的電極上，並透過吸附時間控制吸附量。在電極表面性質分析，首先證明了吸附量隨吸附時間增長而增多，並且自由離子比例也隨之上升。然而孔洞電極的比表面積隨吸附時間上升而下降。接著組成對稱式超級電容器並進行電化學性能測試。超級電容器的比電容值隨著吸附時間增長而呈現先上升後下降的趨勢，並且在吸附時間為10分鐘時為最佳，說明其在離子移動能力與電極表面積上取的了折衷。而其在高功率密度的條件下相較於僅使用添加GO的超級電容器能量密度提升約10%。
綜上所述，透過氧化石墨烯及兩性離子分子的修飾，不僅針對電極與電解質之間的介面進行了改善，同時也修飾了活性碳孔洞內部，完整地增進了離子的移動能力。

Supercapacitors represent a class of energy storage devices situated between batteries and traditional capacitors, characterized by high power density and commendable energy density. The modification of supercapacitor electrode surfaces emerges as a promising approach to significantly enhance their performance under high power density scenarios, thereby elevating their application potential. Graphene oxide (GO), synthesized by modified Hummer’s method, as an additive adds to activated carbon electrodes with varied ratios. The supercapacitor applying the electrodes with 5 wt% GO additive exhibits the best electrochemical performance, which is attributed to a compromise between the free ion ratio and the conductivity. To further improve the performance of supercapacitors, the zwitterionic molecule is adsorbed on the surface of the 5wt% GO-added electrodes with varied adsorption times. The supercapacitor applying the electrode with 10 minutes zwitterionic molecule adsorption exhibits the best electrochemical performance, which is attributed to a compromise between the surface and diffusion capacitance. The supercapacitor with the 5wt% GO-added and 10 minutes of zwitterionic molecule-adsorbed electrode (SC-GO5/Z10) possesses a notable energy density under high power density scenarios, which is 50% higher than pure activated carbon electrode. The added GO enhances the ion movement at the electrode surface. Additionally, the adsorbed zwitterionic molecule further improves the ion movement at the electrode surface and within the pores of activated carbon structures. So far, a comprehensive enhancement in ion movement is achieved along the entire pathway, which significantly improves the supercapacitor performance.

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