从器件角度提高石墨烯基超级电容器体积能量密度的研究

This project is dedicated to improve the volumetric energy density of graphene based supercapacitor from the perspective of the materials, structures and the configuration of the device. In the aspects of electrode materials, macro- and micro- controllable preparation technology is developed to construct graphene based three-dimensional network structures. And then functional materials was used to optimize the volumetric specific capacitance of the electrode materials. In the aspects of electrolyte, according to the 3D network structures of graphene, wide potential window organic electrolyte with different sizes was chosen to study the energy storage mechanism of the electrode material in order to find out the optimal electrolyte for the supercapacitor. In the aspect of the configuration of supercapacitor, different materials for positive and negative electrode was used to study the influence of different configuration on the capacitance and working voltage of the device, which would lead to high voltage supercapacitor fabrication. All in all, in this project, based on the energy density formula E=1/2CV2, volumetric specific capacitance, working voltage and volumetric energy density were thoroughly optimized by adjusting the electrode material, electrolyte and device itself. The expected results obtained in this project would promote the application and the large-scale industrialization of supercapacitor.

本项目致力于从器件角度提高石墨烯基超级电容器的体积能量密度。在电极材料方面，发展微观和宏观织构可控的低成本石墨烯制备技术，利用石墨烯片层构成结构致密的高密度石墨烯基三维网络结构体，同时利用功能性材料优化其电化学性能，提高其体积比电容。在电解液方面，选用电位窗宽的有机系电解液，同时根据石墨烯基三维网络结构体的结构特征，选择多种同类但离子尺寸不同的电解液，研究电极材料的储能机制，选出最合适的有机系电解液。在电容器构型方面，选择合适的正负极材料组装不同构型的超级电容器，从对称型到不对称型，研究构型对电容器电容量和工作电压的影响，组装出高电压超级电容器。总而言之，根据能量密度公式E=1/2CV2，本项目在电极材料上提高其体积比电容，在电解液和电容器配型上提高电容器的工作电压，从器件角度提高超级电容器的体积能量密度，促进超级电容器的广泛应用，进而推动超级电容器的产业化和规模化应用。

以氧化石墨烯为基元材料,在对三维空间中氧化石墨烯的组装过程深入分析的基础上，有针对性地在石墨烯多孔材料形成的各个阶段通过引入不同形式的作用力实现了对其孔结构的调控。在石墨烯三维结构组装过程中或完成后引入复合组分构筑石墨烯复合结构，利用多组分协同效应，充分发挥石墨烯组装结构优势获得了特征鲜明的高密度石墨烯基多孔碳材料，探讨了石墨烯多孔网络的结构特征，研究了其电化学性能。同时研究了基于该石墨烯基复合材料的超级电容器，并优化电解液以及电容器构型，由此达到提高其体积能量密度的目的。