双极性高浓度TEMPO增强的双电层电容器的研究

电解液中引入氧化还原活性物质可提高电容器的能量密度，但仍面临着单活性物质不能同时提高正负两极容量、有机活性物质溶解度低及水系电解液电压窗口窄的问题。本项目采用有单电子结构的2,2,6,6-四甲基哌啶氧化物（TEMPO）作为活性物质，利用其可得电子也可失电子的双极性同时提高两极容量，通过降低熔点得到超高浓度电解液，达到提高浓度、扩宽电压窗口的目的，同时又可规避有机电解液的安全风险。项目将通过调控组成开发出高浓度活性电解液，研究组成对电解液物化性质的影响；研究组分对TEMPO电化学行为的影响，揭示不同浓度电解液中的反应机制；系统研究活性炭微观结构对TEMPO在界面吸附、电子转移、脱附的影响，明确影响性能的关键因素，优化材料结构和性能，构建双电层电容器并评价其电化学性能。目前尚未关于双极性高浓度活性电解液增强的电容器的报道。项目的完成将为开发活性电解液增强的电容器提供新思路。

Introducing redox mediators into electrolyte can enhance the energy density of supercapacitors, but encounters with the issues that single redox mediator cannot improve the capacitance of positive and negative electrodes at the same time, organic mediators have a low solubility, and aqueous electrolyte has a low voltage window. This project employs 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) with single-electron structure as the active mediator, and use its polarity, which can obtain and lose electron, to increase the capacitance of two electrodes at the same time. And highly concentrated electrolyte can be obtained by reducing the melting point, which can achieve the purpose of increasing the concentration and widening the voltage window, and avoid the safety risks of organic electrolyte. The project will develop a high-concentration active electrolyte by adjusting the components, study the influence of components on the physicochemical properties of electrolyte; study the influence of electrolyte components on the electrochemical behavior of TEMPO, reveal the reaction mechanism in different concentrations of electrolyte; systematically study the effect of activated carbon microstructure on the interface adsorption, electron transfer, and desorption of TEMPO, clarify the key factors affecting performance, optimize the structure and electrochemical performance of the materials, construct and evaluate the performance of electrochemical double layer capacitors. There is no report on electrochemical double-layer capacitors enhanced by ambipolar high-concentration active electrolyte. The completion of the project will provide new ideas for the development of capacitors with enhanced active electrolytes.