【摘要】 以生物质风化煤系腐殖酸（LHA）为炭质前驱体,通过溶剂蒸发和KOH活化方法制备了球形活性炭。使用扫描电子显微镜（SEM）、N₂物理吸脱附仪等手段对球形活性炭形貌和孔道结构进行了表征;还将活性炭组装成扣式电容器,进行了充放电容量、循环伏安特性和交流阻抗行为等电化学性能测试。结果表明:所制备的球形活性炭具有良好的球形度,通过少量碱活化后球形活性炭BET表面积为2034 m²/g、总孔容为1.24 cm³/g、平均孔径为2.38 nm。同时,以球形活性炭作为电极材料应用于水系超级电容器后显示了优异的电化学性能,比电容可达到319 F/g,在进行10000次充放电后,比电容保持率为98.9%。此外,球形活性炭相比于颗粒活性炭具有更好的导电性,也展现了更加优异的倍率性能和循环性能。因此说明LHA基球形活性炭是一种有潜在优势的超级电容器材料。更多还原

【Abstract】 Spherical activated carbon has been fabricated via a simple solvent evaporation method followed by an activation process.The natural and renewable biomass material,leonardite humic acid（LHA） is used as the carbon source.The surface morphologies and pore parameters of the carbon spheres were analyzed by scanning electron microscope（SEM） and N₂ physical adsorption-desorption instrument.Symmetric capacitor coin type cells were assembled using two spherical activated carbon electrodes.The electrochemical performance of supercapacitors is characterized by galvanostatic charge-discharge（GCD）,cyclic voltammograms（CV） and electrochemical impedance spectroscopy（EIS） in 6 M KOH electrolyte.The results show that the obtained spherical activated carbon with good sphericity also possess high specific surface area（2034 m²/g） and pore volume（1.24 cm³/g）.Meanwhile,the spherical activated carbon electrode materials exhibit a superior high specific capacitance of 319 F/g at a current density of 0.05 A/g.Remarkably,the sample also has outstanding cycling stability with a capacitance retention of 98.9% after 10,000 cycles.In addition,compared with powdered activated carbon,spherical activated carbon has better conductivity and presents more excellent rate capability and cycle performance.This suggests that the LHA-based spherical activated carbon should be a competitive and promising supercapacitor electrode material.更多还原