煤沥青基碳/石墨烯复合多孔材料的制备及其储能性质研究

The specific surface area, pore structure and doping of the carbon materials have a very important influence on their double layer capacitor performances. This project intends to synthesize the graphene’s three-dimensional assembly microparticles from graphene oxide under hydrothermal conditions and high concentration of reducing agents firstly, and then the water is exchanged by alcohol, tetrahydrofuran and dimethyl formamide to form the organic dispersions of graphene’s three-dimensional assembly microparticles.The organic dispersions of graphene microparticles and the organic dispersions of graphene oxide microparticles induced by adding alkali, salt will be used as three-dimensional scaffold to mix with the organic extract of coal tar pitch. Then the components of coal tar pitch will be adsorbed on the surface of graphene or graphene oxide based on the characteristics of graphene and graphene oxide. Finally, porous carbon composites will be obtained after the solvent removal, drying, carbonization and activation. During the process, the porous asphalt based carbon thin layer will uniformly coat on the surface of graphene via the template effect of graphene sheets, therefore the composite carbon materials exhibit a porous structure formed by large pores formed by accumulation of particles, the mesopores morfrmed by graphene assembly and the micropores formed through activation. The influence of the raw material composition, proportion, various parameters during the production process on the apparent morphologies, microstructures and capacitive properties of porous carbon materials will be investigated detailed and mastered. Furthermore, the relationship between the material's capacitive performance and their microstructures will be elucidated and some foundations for the design and synthesis of electrochemical capacitors electrode's materials with high-performance from coal tar pitch will be established when this project is finished.

碳材料的比表面积、孔结构和掺杂对其双电层电容性能有着至关重要的影响。本项目拟利用氧化石墨烯在水热、高浓度还原剂条件下生成的石墨烯三维组装体微粒，经醇、四氢呋喃和二甲基甲酰胺等溶剂交换后形成分散于有机体系的石墨烯组装体；以及分散于有机体系中的氧化石墨烯经碱、盐诱导生成的氧化石墨烯组装微粒和煤沥青的有机溶剂提取物为原料，通过石墨烯或氧化石墨烯的表面特性对煤沥青组份进行吸附，然后经溶剂蒸发脱除、干燥、碳化和活化后制备多孔复合碳材料。利用石墨烯的模板作用使多孔沥青基碳薄层均匀覆盖于石墨烯表面，这样使复合碳材料具有以颗粒堆积形成的大孔、石墨烯组装形成的中孔和活化形成的微孔构成多级孔结构。掌握原料组成、配比、制备过程中各参数对多孔复合碳材料的表观形貌、微观结构以及电容性能的影响规律，阐明材料微结构与其电容性能的之间的关系。本项目的设立将为以煤沥青为碳源的高性能电化学电容材料的设计与合成奠定一定的基础。

用混酸（70%体积的硫酸和30%体积的硝酸）对煤基沥青进行处理，得到水溶性氧化沥青（PO），引入镍氨离子形成凝胶，在干燥和碳化过程中镍氨配合物充当模板制备了比表面积1871.2 m2/g，孔体积1.17 cm3/g的多孔碳，其比电容（Cs）可达248.1F/g。以水溶性PO为对阴离子合成了聚苯胺，经碳化活化后得到的多孔碳材料的Cs值可达300 F/g；采用二元熔盐LiCl-KCl对煤基沥青进行碳化，经活化后所得产品的Cs值达到281 F/g；在钴镍存在下，制备了石榴状的多孔碳材料，其储锂性能可达600 mAh/g，并且具有良好的倍率性能。从氧化石墨烯制备了高比容量石墨烯，在及少量的二酚存在下（1/80-1/40），制备了Cs可达250F/g的石墨烯凝胶体，并且该材料具有良好的循环稳定性和速率性能；采用先制备苯二胺修饰的石墨烯凝胶，然后用浓硫酸处理的方法得到了纯化的氮掺杂石墨烯，其Cs值可达519F/g，并且显示了良好的稳定性和较大的功率密度；采用浓硫酸处理石墨烯膜的方法得到了具有高体积比容量的石墨烯材料，其体积比容量高达494F/cm3,且倍率性能得到极大的提高。研究了导电高分子基柔性电容器件，以三聚氰胺海绵为基质，通过内串联的方式制备了单个器件可输出3.0V电压的超级电容器；研究了可压缩电容在不同压缩状态下的电化学电容行为。制备了Co(1-x)MoxS2 x=2/3,1/2,1/3三元硫化物对电极材料，研究了材料对DSSC光电转换效率的影响，得到了与铂催化性能相当的非铂对电极催化材料；以模板法制备了半透明的导电聚合物光电池对电极材料，使器件可在双面光照条件下工作，提高了光电转换效率。项目的研究结果为进一步研究沥青基碳与石墨烯的复合、设计新型超级电容器件器件和非铂光电池材料奠定基础。