超电容用多孔碳纳米片的制备、结构和性能

发布时间：2018-05-05 20:28

  本文选题：超级电容器 + 多孔碳纳米片　； 参考：《安徽工业大学》2017年硕士论文

【摘要】：近年来,新型储能元件得到了快速发展,在手机和汽车等行业有潜在的应用前景。其中,超级电容器因其循环寿命长、功率密度高等特点受到了人们的青睐。相对于煤焦油、煤沥青来说,洗油、甲基萘所含成分少,且结构相对简单,可以直接作为构建超电容用多孔碳纳米片的模块。本文分别以洗油、甲基萘为碳源,采用模板法制备多孔碳纳米片。采用氮吸脱附、FESEM和TEM等手段表征所得多孔碳纳米片的结构和形貌。作为电极材料组装成水系纽扣式超级电容器后,采用循环伏安和恒流充放电等技术研究其储电性能。主要结论如下:以洗油为碳源,片状Ca(OH)2作模板协同KOH活化制得了多孔碳纳米片。当洗油质量为8.0 g、Ca(OH)2模板为12.0 g,KOH为12.0 g,加热终温为800℃时,制备的多孔碳纳米片命名为PNS8-12-12-800,其比表面积(SBET)为887 m2/g,微孔表面积(Smic)为720 m2/g,平均孔径(Dap)为2.09 nm。在6 M KOH电解液中,0.05 A/g电流密度下,PNS8-12-12-800的比容高达342.1 F/g,能量密度达11.88 Wh/kg,电流密度增大至20 A/g时,比容为219.4 F/g,显示了很高的容量。在5 A/g电流密度下,经过7000次循环,其容量保持率高达94.7%,表现出好的循环稳定性。以洗油为碳源,nano-CaCO3为模板耦合KOH活化,采用常规加热法制备了不同孔隙结构的多孔碳纳米片。当洗油质量为6.0 g、nano-CaCO3模板为9.0 g,KOH为12.0 g,加热终温为850℃时,制得的多孔碳纳米片命名为PNS6-9-12-850,其平均孔径为7.52 nm,比表面积为1010 m2/g,样品中含有丰富的微孔和中孔。在6 M KOH电解液中,0.05 A/g电流密度下,PNS6-9-12-850初始比容为221.9 F/g,当电流密度从0.05 A/g增大到100 A/g时,比容保持率高达79.4%,显示了极好的速率性能。在0.2 A/g电流密度下,压降IR仅为0.0013 V,显示了很好的导电性。在5 A/g电流密度下,经过9000次充放电,比容仅衰减2.9%。以甲基萘为碳源,nano-CaCO3为模板协同氢氧化钾活化,制得了褶皱多孔碳纳米片。当甲基萘质量为6.0 g、nano-CaCO3模板为6.0 g,KOH为12.0 g,加热终温为900℃时,制备的褶皱多孔碳纳米片命名为SPNS6-6-12-900,其孔径介于1~6 nm之间,比表面积为1136 m2/g。样品SPNS6-6-12-900含有一定量的含氧官能团和少量含氮官能团。在6 M KOH电解液中,0.05 A/g电流密度下,SPNS6-6-12-900比容高达286.5 F/g,电流密度增至100 A/g时,比容保持在167.4 F/g。在5 A/g电流密度下,经7000次循环,比容保持率可达98.4%。可见,褶皱多孔碳纳米片具有卓越的电荷迁移能力和优异的循环稳定性。
[Abstract]:In recent years, new energy storage components have been rapidly developed, and have potential applications in mobile phone and automobile industries. Among them, supercapacitors are favored because of their long cycle life and high power density. Compared with coal tar, coal tar, washing oil and methylnaphthalene contain less components, and the structure is relatively simple, which can be directly used as a module for building porous carbon nanochips for ultracapacitors. In this paper, porous carbon nanochips were prepared by template method using washing oil and methyl naphthalene as carbon source. The structure and morphology of the porous carbon nanoparticles were characterized by means of nitrogen adsorption and desorption (FESEM) and TEM. After the supercapacitors were assembled as electrode materials, the storage performance was studied by cyclic voltammetry and constant current charge-discharge techniques. The main conclusions are as follows: porous carbon nanoparticles were prepared by using washing oil as carbon source, flake Ca(OH)2 as template and KOH activation. When the quality of washing oil is 8.0 g / g, the template is 12.0 g / kg Koh and the final heating temperature is 800 鈩，

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