褐煤-玉米芯基活性炭在双电层电容器中的应用

Application of lignite corncob-based activated carbon in electric double layer capacitor

以褐煤和玉米芯为原料,采用炭化活化法制备了不同原料质量比下的活性炭,对比分析了活性炭比表面积、孔径分布、表面官能团及电化学性能。结果表明,在褐煤与玉米芯原料质量比为3∶1时制得的活性炭性能最佳,比表面积可达1952.9 m^(2)·g^(-1),中孔率为10.1%。将其作为电极材料应用于双电层电容器,以3 mol·L^(-1)的KOH为电解液,在50 mA·g^(-1)电流密度下比电容可达347 F·g^(-1),电流密度达到2 A·g^(-1)时比电容仍保持在260 F·g^(-1)。在1 A·g^(-1)电流密度下循环1000次比电容保持率80.7%,呈现出良好的倍率性与循环稳定性。

Activated carbons with different mass ratios of lignite and corncob were prepared by carbonization and activation.The specific surface area,pore size distribution,surface functional groups and electrochemical properties of activated carbons were compared and analyzed.The results show that,when the mass ratio of lignite to corncob is 3:1,the activated carbon has the best performance,the specific surface area can reach 1952.9 m^(2)·g^(-1),and the mesoporous rate is 10.1%.When it was used as electrode material in electric doublelayer capacitor,with 3 mol·L^(-1) KOH as electrolyte,the specific capacitance can reach 347 F·g^(-1)at the curent density of 50 mA·g^(-1).When the current density reaches 2 A·g^(-1),the specific capacitance sti remains 260 F·g^(-1).At 1 A·g^(-1)current density,the specific capacitance is maintained 80.7% for 1000 cycles,showing good magnification and cycle stability.