本研究利用溶膠-凝膠法(sol-gel method)成功的合成出氧化鎢奈米粒子(nano particle, WOx-p)，經過不同溫度的熱處理後，發現顏色會隨著鍛燒溫度的上升而產生明顯的變化，其粉末會由未經過熱處理的藍色(WOnon-p)變成黃色的氧化鎢(WO400-p)。在空氣中經鍛燒400oC後可形成具有良好結晶結構之氧化鎢奈米粒子(WO400-p)，比表面積為35.9 m2/g。在0.5M的H2SO4電解液中以掃瞄速度25mV/s、操作電位-0.3V~0.5V vs. Ag/AgCl進行循環伏安掃描，其比電容值為53.7F/g，且循環穩定性可高達500圈(以產氫反應發生與否為判斷依據) 。經過高掃描速率500mV/s的電容測試，其比電容值下降了60%。
為了能更加有效的利用氧化鎢奈米粒子，我們期望將氧化鎢奈米粒子以均勻不堆積的方式成長在工作電極上，本研究以具有高導電性(片電阻0.0013Ω/cm2) 、高比表面積(546.4m2/g) 的碳氣凝膠作為骨架，利用濕式含浸法(wet impregnation method) 將氧化鎢奈米粒子(WOnon-p) 以薄薄一層的方式成長於碳氣凝膠骨架之表面上。此複合材料在空氣中經過400oC高溫鍛燒六小時後成為具有良好的結晶結構且比表面積高達710m2/g的氧化鎢/碳氣凝膠複合材料。在0.5M的H2SO4電解液中，掃描速率為25mV/s、操作電位-0.3V~0.5V vs. Ag/AgCl進行循環伏安掃描，扣除碳氣凝膠之貢獻後氧化鎢之比電容值可高達700F/g 。在高掃描速率500mV/s下，循環穩定性至少可達4000圈，比電容值相較於25mV/s的掃描速率而言也僅僅降低31.3%，表示本複合材料具有良好的高速性能 (high rate capacity)。
本研究認為利用濕式含浸法將氧化鎢奈米粒子與碳氣凝膠結合，確實能藉由碳氣凝膠將氧化鎢奈米粒子更均勻且薄的分散在工作電極表面。由於氧化鎢奈米粒子以薄薄一層的方式分散在多孔性的碳氣凝膠骨架上，故能增加電解液與氧化鎢奈米粒子的接觸機會。當我們成長相同量的活性物質於工作電極表面時，本複合材料能更有效的利用到每一個氧化鎢奈米粒子。當電化學反應發生時，在電解液與電極表面發生法拉第反應，電子能快速地透過高導電性的碳氣凝膠傳達至電流收集器上，進而提高氧化鎢奈米粒子的使用效率。
由於本複合材料在掃描速率25mV/s下，當掃描圈數到達第500圈時工作電極表面會有氫氣產生的現象；為了延緩氫氣產生的現象發生，本研究在電解液中加入了不同濃度的碳酸氫鈉(sodium hydrogen carbonate, NaHCO3)。經過循環伏安掃描實驗發現，提升Na+的濃度確實可以延緩氫氣產生的現象發生，但卻會減少複合材料的比電容值，在碳酸氫鈉之濃度為0.06M時，掃描速率為25mV/s下，比電容值減少為620F/g，但循環穩定性卻可高達至少1000圈。
利用氧化鎢/碳氣凝膠所製備而成的對稱式電容器，經過不同電流密度進行充放電的實驗後，其充放電圖形大約對稱，但比電容值偏低且iR drop亦會隨著電流密度的上升而增加。經過公式計算後，得到比能量以及比功率的值分別為：2 Wh/kg、6.23kW/kg，具有成為下世代電容器的潛力。

Tungsten trioxide, a low cost and an environmentally friendly supercapacitive material, is deposited as a thin nanostructure of nanocrystals into carbon aerogels, a mesoporous host template of high specific surface areas and high electric conductivities, with a wet chemistry process. This tungsten trioxide/carbon aerogel composite shows ultrahigh specific capacitances(tungsten trioxide based) of around 700 F/g at a scan rate of 25 mV/s within a potential window of -0.3 to 0.5 V in 0.5M H2SO4 solutions. The composite also possesses an excellent high rate capability manifested by maintaining specific capacitances above 480 F/g at a high scan rate of 500 mV/s, and an outstanding cycling stability demonstrated by a negligible 5% decay in specific capacitances after 4000 cycles.
The success is attributable to the fuller utilization of tungsten trioxide for supercapacitance generation, made possible by the composite structure enabling largely and well exposed tungsten trioxide to the electrolyte and easy transport of charge carriers, ions and electrons, within the composite electrode.
Plain tungsten trioxide electrodes are also investigated. The as-prepared tungsten trioxide nanoparticles are synthesized with a sol-gel process, followed by calcination at 400 oC. The specific capacitances of plain tungsten trioxide electrodes are 53.7F/g at a scan rate of 25mV/s within a potential window of -0.3 to 0.5 V in 0.5M H2SO4 solutions. When the scan rate is increased to 500mV/s, the specific capacitances of the plain tungsten trioxide electrode decrease by 60%.
Symmetric capacitors composed of two tungsten trioxide/carbon aerogel composite electrodes are studied. The specific energy and specific power of this device equal 2Wh/kg and 6.2kW/kg, respectively.
The products have been characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM),X-ray spectroscopy (XPS), wide angle X-ray scattering (WAXS), surface area and pore size analyses (BET), and cyclic voltammetry (CV).

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