物理化学两步活化法制备煤基活性炭电极材料

发布时间：2018-02-16 12:02

本文关键词： 物理化学活化超级电容器煤基活性炭电化学性能　出处：《中国矿业大学学报》2017年04期 　论文类型：期刊论文

【摘要】：为提高超级电容器用的活性炭电化学性能,通过物理化学两步活化法制备煤基活性炭.以太西无烟煤为原料,通过成型和炭化后,用CO_2物理活化制得柱状活性炭(AC-1).将AC-1酸洗脱灰,并用KOH水溶液浸渍,进行第2步化学活化,制得超级电容器用的煤基活性炭(AC-2),两步活化后总收率为45.18%.将活性炭制备成电极材料,并在三电极和双层电容器体系下进行电化学性能测试.结果表明:在KOH电解液浓度为6mol/L,电流密度为0.5A/g时,三电极体系下,比电容由68.5F/g(AC-1)提高到122.5F/g(AC-2),在纽扣式超级电容器体系下,比电容由75F/g(AC-1)提高到165.5F/g(AC-2),且AC-2具有良好的长循环稳定性,经过5 000次的循环后电容量几乎无衰减.与物理活化所得活性炭相比,物理化学两步活化所得活性炭的总孔容和中孔率明显增加,其作为电极材料的电化学性能显著提高.
[Abstract]:In order to improve the electrochemical performance of activated carbon used in supercapacitors, coal-based activated carbon was prepared by physical and chemical two-step activation. A columnar activated carbon (AC-1) was prepared by physical activation of CO_2. The activated carbon (AC-2N) used in supercapacitors was prepared by acid washing of AC-1 and impregnation with KOH aqueous solution. The total yield of activated carbon in two steps was 45.18%. The activated carbon was prepared into electrode material. The results show that the specific capacitance of the three-electrode system is increased from 68.5 F / g to 122.5 F / g AC-2 when the concentration of KOH electrolyte is 6 mol / L and the current density is 0.5 A / g, and the specific capacitance is increased from 68.5 F / g to 122.5 F / g AC-2 in the button-type supercapacitor system. The specific capacitance was increased from 75F / g ~ (-1) to 165.5F / g ~ (-1) AC-2N, and the AC-2 had good long-cycle stability, and after 5,000 cycles, the capacitance had almost no attenuation. Compared with the activated carbon obtained by physical activation, The total pore volume and mesoporous ratio of activated carbon obtained by physicochemical two-step activation were obviously increased, and the electrochemical properties of activated carbon as electrode materials were improved significantly.
【作者单位】：中国矿业大学煤炭加工与高效洁净利用教育部重点实验室化工学院;
【基金】：国家自然科学基金项目(21506248) 江苏省基础研究计划(自然科学基金)项目(BK20130171) 中央高校基本科研业务费专项资金项目(中国矿业大学,2013QNA16) 江苏省煤基CO2捕集与地质储存重点课题(6AT147802)
【分类号】：O646.54;TQ424.1

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