聚丙烯酸鈉水凝膠作為電解質具有相當潛力。因為聚丙烯酸鈉水凝膠不僅製造成本低廉，而且擁有良好的膨潤度和帶負電荷的特性，因此受到了關注。然而觀察其他文獻，我們發現聚丙烯酸鈉水凝膠由於水合能力不足，導致其電位視窗較窄，且無法快速響應電場，因此表現受到限制。為了克服這些限制，本研究加入帶有正電荷的物質（META）形成雙離子，以提高水合能力和建立離子通道，從而拓寬電位視窗並加快對電場的響應速度。透過FTIR、DMA、Raman以及EIS分析評估了水凝膠的官能基、機械強度、水合能力和導離度等特性。根據分析結果，形成雙離子後，水凝膠的水合能力得到增強，並且導離度從60.3 mS cm-1提升至72.8 mS cm-1，同時機械強度也獲得不錯的提升。
隨後組成對稱式碳電極的超級電容器進行電化學分析，在CV的分析中，電位視窗已從原本的1 V提升至1.2 V，此外在高掃描速率下，PMA超級電容器的表現優秀於PAA超級電容器。接著在0.5 A g-1的充放電速率下，PMA超級電容器的比電容高出PAA超級電容器一倍，達到了114 F g-1，並且能量密度與功率密度為24.99 Wh kg-1和587.46 W kg-1。最後進行了彎折45°、90°的電化學測試，PAA超級電容器的CV面積比和GCD的電容保存率僅達到83.85%和82.37%，而PMA超級電容器在這兩個方面均超過了90%，展現出良好的電化學性能。因此本研究成功地提升了聚丙烯酸鈉水凝膠的機械強度和電化學表現。

In this study, acrylic acid (AA) based zwitterionic hydrogel is employed for improving the flexibility and performance for the symmetric carbon supercapacitors. The neutralization between AA and sodium hydroxide is carried out for sodium acrylate (SA). The polymerization of SA is performed for obtaining anionic polymer (PAA). The copolymerization of [2-(acryloyloxy)ethyl]trimethylammonium chloride (META) and SA is performed for obtaining zwitterionic polymer (PMA). Both PAA and PMA are confirmed by Fourier-transform infrared spectra. Both PAA and PMA hydrogel electrolytes are prepared by the intake of 1 M Na2SO4. Ionic conductivity of PMA hydrogels have lower impedance than PAA by electrochemical impedance analysis. PMA and PAA hydrogel electrolytes are sandwiched by activated carbon electrode to make PMA and PAA supercapacitors for electrochemical impedance analysis, cyclic voltammetry and galvanostatic charge/discharge. The electrochemical window of PMA supercapacitors increases to 1.2 V. PMA supercapacitors show specific capacitance of 114 F g−1, which are nearly twice the performance of PAA supercapacitors. Under bending different angles, PMA supercapacitors have over 90% capacitance retention.

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