摘要
煤炭作为一种来源广泛的非金属矿物,是制备大量多孔碳的理想原料。本文以1/3焦煤为原料,NaOH和KOH为活化剂,制备了多孔碳,并研究了硫/多孔碳复合正极材料的电化学性能。结果表明:采用NaOH和KOH单独活化时制备的多孔碳比表面积很大,分别为1649 m^2/g和1867 m^2/g,而采用NaOH和KOH混合活化制备的多孔碳比表面积大幅度下降,当NaOH与KOH质量比为1∶1活化时多孔碳的比表面积最小,为290 m^2/g。电化学测试表明,NaOH与KOH质量比为1∶1混合活化的硫/多孔碳正极材料的电性能优于NaOH和KOH单独活化的硫/多孔碳正极材料,0.2 C下首次放电比容量为790 mA·h/g,库仑效率为93.16%,100次循环后放电比容量为740 mA·h/g。还分析讨论了煤基多孔碳孔径分布对电化学性能的影响。
As a non-metallic mineral with a wide range of sources,coal is an ideal raw material for the preparation of porous carbon.A porous carbon was prepared by 1/3 coking coal as raw material using NaOH and KOH as activators,and the specific electrochemical properties of sulfur/porous carbon composite cathode material were analyzed.The results show that the porous carbon prepared by the activation of NaOH or KOH alone has a specific surface area of 1649 m^2/g and 1867 m^2/g,respectively.The specific surface area of porous carbon activated by the mixture of NaOH and KOH is greatly reduced.When the mass ratio of NaOH to KOH is 1∶1,the specific surface area of porous carbon is least which is 290 m^2/g.The electrical properties of sulfur/porous carbon composite cathode material activated by 1∶1 mass fraction of NaOH to KOH mixed activation are better than other cathode materials activated by NaOH and KOH respectively.The first discharge capacity is 790 mA·h/g at 0.2 C and the coulombic efficiency is 93.16%.The discharge capacity is as high as 740 mA·h/g after 100 cycles.The effect of coal-based porous carbon pore size distribution on electrochemical performance was also analyzed.
作者
杨绍斌
夏英凯
刘凤霞
董伟
沈丁
YANG Shaobin;XIA Yingkai;LIU Fengxia;DONG Wei;SHEN Ding(College of Material Science and Engineering,Liaoning Technical University,Fuxin 123000,China)
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2020年第3期716-723,共8页
Acta Materiae Compositae Sinica
基金
国家自然科学基金(51774175)
关键词
1/3焦煤
锂硫电池
多孔碳
电性能
正极材料
1/3 coking coal
lithium-sulfur battery
porous carbon
electrical properties
cathode material
