【摘要】 采用沥青焦为原料,以NaOH化学活化法制备出不同碱炭比(R)系列活性炭.用氮气吸附和脱附等温线计算出BET比表面积、DFT孔径分布及孔容,并且通过直流循环充放电、循环伏安等表征方法研究了其电化学性能.实验结果表明,R值对活性炭的BET比表面积、DFT孔径分布及孔容有良好的调控作用:当R=5时,其最大BET比表面积为1089m2/g,孔容达0.53cm3/g,当R=3时,其孔径分布在1.0-2.0nm百分比达36.2%;其直流循环充放电曲线较好,循环伏安曲线也近似矩形,表明具有良好双电子层电容器电极材料特性,在3mol/L的KOH电解液体系中,最大质量比电容、体积比电容、单位面积比电容分别达202F/g、143F/cm3、32.9μF/cm2;在1mol/L(C2H5)4NBF4/Propylene Carbonate(PC)电解液体系中,最大质量比电容、体积比电容、单位面积比电容分别达149F/g、107.3F/cm3、20μF/cm2.对KOH和(C2H5)4NBF4/PC电解质吸附的最佳孔径分别为1.3nm,1.5nm左右.更多还原

【Abstract】 A series of petroleum coke-based activated carbons(ACs) were prepared by chemical activation method in different NaOH/petroleum coke ratios(R) .Pore properties of these activated carbons including the BET specific surface area,pore diameter,pore size distribution and pore volume were characterized by DFT method based on N2 adsorption/desorption isotherm.Electrochemical performances were characterized by chronopotentiograms,cyclic voltammetry,ad so on It is found that the NaOH/petroleum coke ratio(R) can control the BET specific surface area and DFT pore size distribution well.When R = 5,the BET specific surface area and pore volume reach 1089 cm2 /g and 0.53 cm3 /g respectively.When R = 3,the percentage of pore diameter ranged from 1.0 to 2.0 nm is 36.2% .The study shows that the AC(R = 3) exhibits a good performance as an electrode material of electric double layer capacitors(EDLCs) since the charge-discharge curve is good and the cyclic voltammetry curve approximates to rectangle.The maximum quality,volume and unit surface area specific capacitance obtained in 3 mol/L KOH are 149F/g,107.3F/cm3,and 20 μF/cm2 and those in 1 mol/L(C2H5) 4NBF4 /propylene carbonate(PC) electrolytic solution are 149F/g,107.3F/cm3 and 20 μF/cm2.are equal to about 202 F/g,143 F/cm3 and 32.9 μF/cm2.The optimum adsorption pore diameters of KOH and(C2H5) 4NBF4 /PC electrolyte are 1.3 nm and 1.5 nm respectively.更多还原