【作者】 高毅；

【导师】 封伟；

【作者基本信息】 天津大学 ， 材料学， 2017， 硕士

【摘要】 能量密度和功率密度是电储能器件的两个重要指标,复合电容器结合了电池和电容器的工作原理,可以同时具有较高的能量密度以及较的高功率密度。具有较高比表面积的碳材料是最常见的正极活性物质,然而其储能机理限制了能量密度的进一步提高,在大电流下多空结构的破坏也限制了其倍率性能的发挥。导电聚合物是另一种常见的电容器正极材料,其特殊的储能机理使其性能具有广阔的提升空间。本文采用苯胺(ANI)与2-氨基对苯二甲酸(ATA)共聚的方法将羧基引入到聚苯胺分子链上以调节分子链的电子结构以及分子之间的相互作用,提高材料的电化学性能。两种单体的投料比对材料的形貌具有重要的影响,当ANI/ATA的比例为8:2时,产物为规整的一维纳米棒,这有助于充放电过程中阴离子的扩散。当ANI/ATA的比例为8:2时,共聚物表现出最佳的电化学性能,最大放电电流达到50A/g,在2A/g的电流下循环1000圈后容量保持率达到78.5%,在20mA/g的电流下198F/g。良好的倍率性能以及阴离子掺杂/解掺杂的电荷存储机理使得这种共聚物可以作为HSC的正极材料。采用中间相碳微球作为HSC的负极材料,体系获得了最高的能量密度(153.9 Wh/kg),采用钛酸锂作为负极材料,体系获得了最高的功率密度(3011.5 W/kg)。更多还原

【Abstract】 Energy density and power density are two important elements for electric energy reservation.Hybrid supercapacitors（HSC）combine the working principles of batteries and capacitors and hence mast the high energy and power density simultaneously.Carbonous materials with high specific surface area are the common cathode material for HSC.However,its physical energy storage mechanism limits capacitance properties.Besides,the microporous structure further undermines the capacitive reaction at high current densities.Conducting polymers are also the important cathode materials of HSCs for their pristine high electronic conductivities and the special energy store mechanism derived from the doping/dedoping anions with favorable kinetics.Here,aniline（ANI）and2-aminoterephthalic acid（ATA）were synthesized by the chemical oxidation polymerization at different molar ratios of monomers（ANI/ATA）.The appropriate amount of carboxyl groups enabled the delocalization of charge along the polymer backbone and the intermolecular forces.The copolymer synthesized at ANI/ATA value of 8:2 exhibited the morphology of regular nanorods,which is benefit for the anions diffusion.The best electrochemical performances of high specific capacitance（198 F/g at the current density of 20 mA/g）,excellent rate capability（the maximum current density of 50 A/g）,and excellent cycling stability（capacitance retention of 78.5%after 1000 cycles at 2 A/g）were gotten with the ANI/ATA value of 8:2.The energy density of 153.9 Wh/kg and the power density of 3011.5 W/kg of HSCs are obtained with commercial meso-carbon microbeads（MCMBs）and Li₄Ti₅O₁₂（LTO）as anode materials,respectively.更多还原