采用Mg(OH)2模板策略结合原位KOH活化法合成出超级电容器用煤沥青基多孔炭(PCs).运用透射电子显微镜、拉曼光谱仪、X射线光电子能谱仪和N2吸脱附技术对PCs进行表征.利用恒流充放电、电化学阻抗谱和循环伏安法对PCs的电化学性能进行研究.结果 表明,PC具有大的比表面积(3 145m2g-1)和大量的短孔.当作为超级电容器的电极材料时,在6 mol L-1 KOH电解液中,在0.05 A g-1电流密度下,显示出272 F g-1的高比电容;在20 A g-1电流密度下,比电容为217 F g-1,呈现好的倍率性能;经10000次充放电循环后,其比电容保持率为96.69％,展现出优异的循环稳定性.本工作为高性能超级电容器用沥青基多孔炭的制备提供了一种简单的方法.%Porous carbons (PCs) for supercapacitors were synthesized by a combined Mg (OH) 2 templating and in-situ KOH activation method using coal tar pitch as the carbon precursor,and were characterized by TEM,Raman spectroscopy,XPS and N2 adsorption.Their electrochemical properties were investigated by galvanostatic charge-discharge,electrochemical impedance spectroscopy and cyclic voltammetry.Results show that the specific surface area of the PCs increases with the KOH dosage and exhibits a maximum with an activation temperature at 800 ℃.The optimum PC has a high surface area up to 3145 m2 g-1 with abundant micropores,and exhibits a high specific capacitance of 272 F g-1 at 0.05 A g-1,a rate capability of 217 F g-1 at 20 A g-1 and a good cycle stability with a 96.69％ capacitance retention after 10000 cycles in a 6 M KOH electrolyte.This work provides a simple method for the large-scale production of PCs from pitch-based carbon sources for high-performance supercapacitors.
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