Graphene-based, two dimensional porous ionic polymer networks and carbon nanosheets for supercapacitors

石墨烯因其高的最大比表面积、优异的导电性和二维电荷传输能力而被认为是最有前途的超级电容器电极材料之一。然而，石墨烯纳米片表现出高度的重新聚集和堆积的趋势。这种不可避免的团聚和堆积显著降低了超级电容器的电化学活性表面积，从而导致超级电容器性能的恶化。在本项目中，我们提出将石墨烯与多孔离子聚合物功能化，生成石墨烯基多孔离子聚合物骨架，结合石墨烯和多孔离子聚合物的优点来提高超级电容器的性能。石墨烯的2D结构允许在两侧生长均匀的多孔离子聚合物外壳。从而可以有效地抑制石墨烯片层的聚集和再堆积。利用石墨烯的高导电性，可以提高石墨烯基多孔离子聚合物骨架的导电性。同时，多孔聚合物壳将赋予基于石墨烯的多孔聚合物骨架假电容。由于构建块的选择和设计具有广泛的灵活性，因此多孔聚合物的孔结构和孔参数可以定制。研究了石墨烯类多孔离子聚合物骨架的储能机理以及石墨烯与多孔离子聚合物之间的协同效应。此外，离子聚合物还可以作为制备炭质材料的前驱体。与传统的聚合物前驱体相比，具有本征离子性质和离子对中具有较强库仑相互作用的带电聚合物可能会导致前驱体具有较高的热稳定性，从而减少分解过程开始前的质量损失。因此，基于石墨烯的离子聚合物可以作为前驱体来制备用于超级电容器的多孔碳纳米片。通过改变TECTON可以将各种杂原子结合到碳纳米片中。系统地研究了不同杂原子碳纳米片的超级电容性能。合成工作将在南昌的设备实验室伍珀塔尔进行。

Graphene is considered as one of the most promising candidates for the electrode materials of supercapacitors due to its high maximum specific surface area, superior electrical conductivity, and two-dimensional (2D) charge transport ability. However, graphene nanosheets show a high tendency for reaggregation and stack together. This inevitable reaggregation and stacking significantly decreases the electrochemically active surface area, thus resulting in a deteriorated supercapacitor performance.In this project, we propose to functionalize graphene with porous ionic polymers to generate graphene-based porous ionic polymer frameworks, which integrate the advantages of both graphene and porous ionic polymers to improve the performances of supercapacitors. 2D structure of graphene allows for the growth of uniform porous ionic polymer shells onto both sides. Thereby, the aggregation and restacking of the graphene sheets can be effectively suppressed. The conductivity of the graphene-based porous ionic polymer frameworks can be increased by taking the advantage of the high electrical conductivity of graphene. Meanwhile, the porous polymer shells will endow graphene-based porous polymer frameworks with pseudocapacitance. The porous structure and pore parameters of porous polymers can be tailored owing to the wide-ranging flexibility in the choice and design of building blocks. The energy storage mechanism of graphene-based porous ionic polymer frameworks and the synergistic effect between graphene and porous ionic polymers will be investigated. Besides, ionic polymers could be used as precursors for the preparation of carbonaceous materials. Compared with conventional polymeric precursors, charged polymers with intrinsic ionic nature and strong Coulombic interactions in ionic pairs may lead to high thermal stability of the precursor, which reduces mass loss before the decomposition process begins. Thereby, graphene-based ionic polymers could be used as precursors to prepare porous carbon nanosheets for use in supercapacitors. Various heteroatoms can be incorporated into the carbon nanosheets by changing the tectons. The supercapcitor performance of the carbon nanosheets with different heteroatoms will be systematically investigated.The synthetic work will be done in Wuppertal, the device work in Nanchang.