Supercapacitor (電容材料)
The increased energy demand has prompted the search of not only renewable energy but also efficient energy storage devices. Because of the merits of high power density, fast charge/discharge ability, and long cycle life, supercapacitors have emerged as promising energy storage devices. To achieve high charge capacity, the nature of the electrodes should be of high conductivity, surface area, and electrochemical stability. Among the various conducting materials for applications as the electrode materials in supercapacitors, conducting polymers such as polyaniline (PANI) have the advantages of low cost and low environmental impacts.
However, the electrochemical stability is generally a limitation of conducting polymers. To overcome this problem, we have incorporated the rigid and nonplanar pentiptycene scaffolds into PANI to improve the electrochemical stability and meanwhile to enhance the specific capacitance. By restricting the chain motions of polyanilines, the stability after 1000 consecutive charging-discharging cycles are highly enhanced. An evidence on SEM study shows that the degree of contour blurring and volume change of the nanogranules are relatively minor for the pentiptycene-substituted polyaniline. Furthermore, the accompanied enhancement in capacitance and conductivity might indicate that the clipping of polymer chains facilitates interchain π-π stacking interactions and thus interchain conductivity. Further studies on enhancing specific capacitance and capacitance retention are in progress.
However, the electrochemical stability is generally a limitation of conducting polymers. To overcome this problem, we have incorporated the rigid and nonplanar pentiptycene scaffolds into PANI to improve the electrochemical stability and meanwhile to enhance the specific capacitance. By restricting the chain motions of polyanilines, the stability after 1000 consecutive charging-discharging cycles are highly enhanced. An evidence on SEM study shows that the degree of contour blurring and volume change of the nanogranules are relatively minor for the pentiptycene-substituted polyaniline. Furthermore, the accompanied enhancement in capacitance and conductivity might indicate that the clipping of polymer chains facilitates interchain π-π stacking interactions and thus interchain conductivity. Further studies on enhancing specific capacitance and capacitance retention are in progress.
隨著經濟的發展，人類對於能源的需求持續增加，除了開發再生能源的技術外，有效儲能裝置的開發亦是趨勢之一。在各式儲能裝置中，超級電容器具有高功率密度、快速充放電及高充放電循環次數的優點，使其在近10年受到高度的重視。在電極材料的選擇上，材料本身的導電度、表面積及電化學穩定性都是必須考量的因素。目前已有多種導電高分子被研究，初步研究成果顯示導電高分子皆有電化學穩定性問題。為了改善這個問題，我們在聚苯胺導電高分子的骨架中引入了剛硬且非平面性的五苯荑，藉以提升聚苯胺的穩定性及電容表現。在引入五苯荑後，聚苯胺分子鏈的運動被限制，使得修飾後的聚苯胺在循環穩定度上有所提升。透過SEM電子顯微鏡的觀察，我們發現修飾後的聚苯胺在1000次充放電後，其奈米結構不像未修飾的聚苯胺那樣有明顯的膨脹變大。此外，電容值及導電度的提升也反映出五苯荑架構促進了聚苯胺分子間的π-π堆積作用。更多有關提升電容及穩定度的研究正在持續中。
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Synthesis, Structural Characterization, and Electrochemical Properties of Isotruxene–Polyaniline Hybrid Systems.
Tan, W. S.; Lin, S.-Y.; Yang, J.-S.
J. Chin. Chem. Soc. 2017, 64 (9), 1007-1022.
Iptycene Substitution Enhances the Electrochemical Activity and Stability of Polyanilines.
Tan, W. S.; Lee, T.-Y.; Hsu, Y.-F.; Huang, S.-J.; Yang, J.-S.
Chem Comm. 2018, 54 (43), 5470-5473.
Tan, W. S.; Lin, S.-Y.; Yang, J.-S.
J. Chin. Chem. Soc. 2017, 64 (9), 1007-1022.
Iptycene Substitution Enhances the Electrochemical Activity and Stability of Polyanilines.
Tan, W. S.; Lee, T.-Y.; Hsu, Y.-F.; Huang, S.-J.; Yang, J.-S.
Chem Comm. 2018, 54 (43), 5470-5473.