【作者】 吴娟；

【导师】 王开学； 陈接胜；

【作者基本信息】 上海交通大学 ， 化学， 2011， 硕士

【摘要】 超级电容器是一种新型的储能元件,由于它具有充放电速度快、功率密度高、循环寿命长、免维护、环境友好等特点,受到国内外科学家的广泛关注。其中提高电极材料的比电容值和循环寿命,是获得更高性能超级电容器的关键因素。本论文以获得高性能的超级电容器电极材料为目标,采用电化学方法和化学方法分别制备了三种复合材料,介孔碳纳米线/聚苯胺、介孔碳/聚苯胺和石墨烯/聚苯胺,研究了三种材料的结构和形貌,并作为超级电容器电极材料对其电化学性能进行测试,主要研究内容有:（1）首先采用AAO作为模板,将F127和酚醛树脂的乙醇溶液引入到AAO的孔道中,室温下待乙醇完全蒸发后,放入烘箱中进行老化,然后在氮气保护下煅烧,进行碳化,再用盐酸将AAO模板除掉,制得介孔碳纳米线,采用SEM和TEM手段对其结构和形貌进行了表征。研究了时间对去除模板的影响,并通过SEM来观察在不同时间下模板的去除效果。（2）以介孔碳纳米线为基体,通过电化学方法制备了新型聚苯胺/介孔碳纳米线（PANI/MCFs）复合材料,采用SEM、TEM和TGA等手段对样品的结构、形貌和组成进行了表征。并将PANI/MCFs复合材料组装成三电极体系超级电容器,用循环伏安、恒流充放电、交流阻抗等方法对材料的电化学性能进行了测试分析。结果显示,在1.0 mol/L H₂SO₄溶液中,当扫描速率为50 mA/g时,复合材料的比容量达到391 F/g,与纯聚苯胺相比,其循环稳定性也得到显著提高.（3）化学法合成了介孔碳,然后将介孔碳在盐酸溶液中超声分散均匀,后利用化学法在溶液中引发新蒸苯胺单体聚合,得到介孔碳和聚苯胺的复合材料（MC/PANI）,采用XRD手段对其进行表征。将介孔碳、纯聚苯胺和聚苯胺/介孔碳复合材料分别组装成三电极体系超级电容器,用循环伏安、恒流充放电、交流阻抗等方法对材料的电化学性能进行了测试。结果显示,在1.0 mol/L H₂SO₄溶液中,介孔碳电极材料的循环稳定性最好,但比容量只有98.5 F/g,随着循环次数的增加,聚苯胺电极材料的衰减最为严重,循环1000次后比容量保持率只剩44.5%,而介孔碳/聚苯胺复合材料的比容量在电流密度为10 mA/g时达到593 F/g,其循环稳定性比单纯的聚苯胺得到明显改善,循环1000次后比容量保持率为81.3%。（4）采用优化了的Hummers法合成了石墨烯,然后将石墨烯超声分散均匀,利用化学法在溶液中引发新蒸苯胺单体聚合,得到石墨烯和聚苯胺的复合材料（GNS/PANI）,采用XRD和拉曼光谱对其进行表征。将石墨烯和复合材料分别组装成三电极体系超级电容器,用循环伏安、恒流充放电、交流阻抗等方法对其电化学性能进行了测试。结果显示,在1.0 mol/L H₂SO₄溶液中,相同电流密度下,石墨烯/聚苯胺复合材料的比容量要比纯石墨烯的比容量高的多,说明聚苯胺的存在大大提高了复合材料的比容量,而且复合材料中石墨烯的存在使得复合材料的循环稳定性比单纯的聚苯胺做为超级电容器电极材料时循环稳定性要好的多。更多还原

【Abstract】 Supercapacitor is a new type energy storage device. With rapid charge-discharge energy storage, long cycle life, free of maintenance and environmental benign, supercapacitor has attracted considerable attention.The performance of supercapacitors largely depends on the specific capacitance and the cycle life of electrode materials. This dissertation focused on the exploration of new electrode materials with high supercapacitance performance. Three composite materials were prepared through electrochemical and chemical methods, Mesoporous carbon nanofibers/Polyaniline（MCFs/ PANI ） , Mesoporous carbon/Polyaniline （ MC/PANI ） and Graphene/Polyaniline（GNS/PANI）, and made a research of their surface morphology and structure through SEM, TEM and XRD, and electrochemical performance through cyclic voltammetry （CV）, galvanostatic charge–discharge and Nyquist impedance test with a three-electrode system. The main works are as follows:（1） Mesoporous carbon nanofibers （MCFs） was prepared using AAO as hard template, the solution of F127 and phenolic resin`s ethanol solution was dipped into the mesoporous of AAO, and then aged in oven, calcinated in N2 to carbonization and then got rid of AAO template through HCl solution. The surface morphology and structure of MCFs were characterized by scanning electron microscope （SEM） and transmission electron microscope （TEM）. The paper also made a research of the influence of time in dissolving AAO template, and observed the result at different time through SEM.（2）Polyaniline （PANI） was prepared within the mesopores and on the surface of mesoporous carbon nanofibers （MCFs） by an electrochemical polymerization method, leading to the formation of a composite material PANI/MCFs. The surface morphology and structure of the composite material were characterized by scanning electron microscope （SEM） , transmission electron microscope （TEM） and thermogravimetric analysis （TGA）. The supercapacitance performance of PANI/MCFs was investigated by cyclic voltammetry （CV）, galvanostatic charge–discharge and Nyquist impedance test with a three-electrode system in 1.0 mol/L H<sub>2</sub>SO<sub>4</sub> solution. The specific capacitance of the composite material was as high as 391 F/g at a current density of 50 mA/g. The cycling stability was much better than that of pure polyaniline.（3）Mesoporous carbon was prepared through chemical method, and aniline was initiated polymerization in the acid solution which contained mesoporous carbon that was already made. A composite of mesoporous carbon/polyaniline （MC/PANI） was prepared, and its structure was characterized by XRD. The supercapacitance performance of MC, pure PANI and MC/PANI composite were investigated by cyclic voltammetry （CV）, galvanostatic charge–discharge and Nyquist impedance test with a three-electrode system in 1.0 mol/L H<sub>2</sub>SO<sub>4</sub> solution. Results show that the cycle stability of MC was the best but the specific capacity was the lowest, 98.5 F/g. With the increase of cycle number, the capacity decay of PANI electrode material was the most serious. There was only 44.5 percent specific capacity left, however, the specific capacitance of the composite material MC/PANI was as high as 593 F/g at a current density of 10 mA/g. And the cycle stability was much better than that of pure PANI, the specific capacity was 81.3 percent left after one thousand cycle numbers.（4） Graphene（GNS） was prepared through optimized Hummers method. Then aniline was initiated polymerization in acid solution which contained graphene that was already well-distributed ahead of time. A composite of GNS/PANI was obtained, and the structure and components were characterized by XRD and Raman spectra. The supercapacitance performance of GNS and GNS/PANI composite were investigated by cyclic voltammetry （CV）, galvanostatic charge–discharge and Nyquist impedance test with a three-electrode system in 1.0 mol/L H<sub>2</sub>SO<sub>4</sub> solution. Results show that the specific capacity of GNS/PANI was much higher then that of pure graphene at the same current density. It revealed that the existence of PANI in the composite improved the electrote material`s specific capacity greatly, and the existence of graphene made the cycle stability of the composite much better than that of pure PANI.更多还原