煤沥青基三维多孔炭作为超级电容器电极材料的电化学性能

Electrochemical properties of coal pitch-based three-dimensional porous carbon as electrode materials for supercapacitors

以廉价的煤沥青为原料,加入造孔剂,依次经过混合工艺、空气氧化稳定化工艺、炭化工艺得到三维骨架结构的炭材料,再经过水蒸气活化,得到高比表面积的多孔炭材料。通过热重分析和元素分析研究沥青和空气氧化稳定化、炭化后样品的热反应特性和组成结构的变化;利用扫描电子显微镜、比表面积分析仪和电化学工作站等对活化后样品表面形貌、孔结构和电化学性能进行表征。水蒸气活化后的多孔炭比表面积可达到1638 m^(2)/g。以此多孔炭为超级电容器电极材料,制备的水系双电层电容器循环性能良好,1 A/g电流密度下比电容可达252 F/g,经过10000次循环后,比容量仍能保持97.3%。因此,该方法制备的多孔炭材料价格低廉、化学稳定性好,可作为一种理想的超级电容器电极材料。

Using cheap coal pitch as raw material and adding pore-forming agent,the carbon material with three-dimensional skeleton structure was obtained by mixing process,air oxidation stabilization process and carbonization process successively,and then the porous carbon material with high specific surface area was obtained by water vapor activation.Thermogravimetric and elemental analysis were used to study the thermal reaction characteristics and structural changes of the samples after oxidation stabilization and carbonization.The surface morphology,pore structure and electrochemical properties of the activated samples were characterized by scanning electron microscope,BET method and electrochemical workstation.After water vapor activation,BET of porous carbon can reach 1638 m^(2)/g.The water-based double layer capacitors prepared with this porous carbon as the electrode material of supercapacitors have good cyclic performance,and the specific capacitance can reach 252 F/g at 1 A/g current density.After 10000 cycles,the specific capacity can still maintain 97.3%.Therefore,the porous carbon materials prepared by this method have low cost and good chemical stability,and can be used as an ideal electrode material for supercapacitors.