剥离/静电自组装制备二氧化锰/石墨烯纳米间层复合材料及其电化学电容性能研究

As novel energy storage devices, supercapacitors have attracted great interest due to their high power density and cycleability. Birnessite-type layered manganese oxide has high specific capacitance, but its poor electrical conductivity results in low rate capability. Graphene has excellent electrical conductivity but low specific capacitance. In this project, layered manganese oxide and graphene will be exfoliated into nanosheets and then adsorbed with opposite charge, respectively. Then manganese oxide/graphene nano-multilayer film will be fabricated by electrostatic layer-by-layer assembly process, the kinetics process and electrochemical capacitive mechanism of nano-multilayer films will be studied by electrochemical quartz crystal microbalance (EQCM) technique. Furthermore, manganese oxide/graphene nano-scale layer-by-layer composite powder material will be prepared by electrostatic self-assembly process. In order to realize nano-scale layer-by-layer self-assembly process, the optimum experimental condition such as kinds and amount of charged agent, mixed process between manganese oxide and graphene nano-sheet colloidal solution will be explored in detail, the layer-by-layer contact between manganese oxide and graphene nano-sheet will extramly promote the electrical conductivity of composite material by graphene, the relationship between the micro-structure and electrochemical capacitance of composite material will be explored by various measurements.

超级电容器是一种新型储能器件，具有很高的功率密度，近年来发展十分迅速。层状二氧化锰材料具较高的比电容，但其导电性能欠佳影响其倍率放电性能。石墨烯材料具有良好的导电性能，但其比电容较低。本项目拟将层状二氧化锰和石墨烯分别剥离为纳米片层，并使其带相反电荷，利用静电层层自组装技术制备层状二氧化锰片/石墨烯片的纳米间层复合膜，采用电化学石英微天平技术研究静电自组装的动力学过程和复合膜的电化学电容机理。在此基础上，通过静电自组装制备层状二氧化锰片/石墨烯片的纳米间层复合粉末材料，探索制备条件（如荷电试剂种类和用量、两种剥离纳米片层溶胶的混合方式及反应时间）和复合材料中二氧化锰/石墨烯纳米片层的相对位置之间的关系，使二氧化锰和石墨烯纳米片层有最大的面接触，充分发挥石墨烯对二氧化锰电导率的贡献，利用各种测试手段，研究纳米复合材料的微观结构与其电化学电容之间的关系。

超级电容器是一种新型储能器件，具有很高的功率密度和循环寿命，近年来发展十分迅速。二氧化锰材料具较高的比电容，但其导电性能欠佳影响其倍率放电性能。石墨烯材料具有良好的导电性能，但其比电容较低，将两者复合可以克服各自的缺点，但复合方式会影响材料的电化学电容性质。本项目将层状二氧化锰和石墨烯进行剥离，并使其带相反电荷，通过静电自组装实现了层状二氧化锰片/石墨烯片的纳米间层复合，材料具有良好的电化学电容性质，项目探索了层状二氧化锰片/石墨烯片的静电自组装条件，研究了各种因素特别是动力学条件对二氧化锰/石墨烯纳米复合材料的电化学电容性质的影响。采用相同合成策略，用静电层层自组装法制备了钴铝水滑石/石墨烯纳米复合材料，研究了材料的电化学电容性质。. 2D石墨烯比表面大、导电性能好，是理想的超低电容器电极材料，但石墨烯容易团聚，影响其电容性质的发挥，3D结构可以避免石墨烯的团聚，N掺杂有利于改善石墨烯的赝电容。本项目分别采用水热法、蒸面包法由氧化石墨烯溶胶制备了N掺杂3D石墨烯，采用气体发泡法用葡萄糖为前驱体制备了N掺杂3D石墨烯，利用超分子化学组装法制备了碳纳米粒子修饰石墨烯，研究了系列改性石墨烯的电化学电容性质。. 活性炭材料是商业化的超级电容器材料，其孔结构对其电容性质影响较为复杂。本项目用废弃物PET制备了用于超级电容器的杂原子掺杂活性炭材料，采用模版法制备了纳米隧道嵌入的分级孔炭材料，采用酶交联处理虾壳制备了多级孔炭材料，用ZnCl2活化氯化铵共热霉菌微生物制备了活性炭，研究了超级电容器用活性炭材料的一系列制备方法，探索了分级孔结构对活性炭材料电容性能的影响。