活化剂用量对竹基活性炭孔结构及电化学性能的影响  

Effect of Activator Dosage on Pore Structure and Electrochemical Properties of Bamboo-based Activated Carbon

作　　者：陈名柱[1] 刘洪波[1] 张东升[2] 邓丛静[2] 夏笑虹[1] 何月德[1] 

机构地区：[1]湖南大学材料科学与工程学院,湖南长沙410082 [2]国家林业局林产工业规划设计院,北京100010

出　　处：《林产化学与工业》2011年第4期63-68,共6页Chemistry and Industry of Forest Products

基　　金："十一五"国家科技支撑计划资助(2006BAD19B06)

摘　　要：以毛竹为炭前驱体,KOH作活化剂,通过调节KOH用量在相同活化条件下制备了具有不同孔隙结构的竹基活性炭材料,通过扫描电镜、BET氮气吸附、直流充放电、交流阻抗和循环伏安等结构与电化学性能分析方法,考察了碱炭比对竹基活性炭材料结构和性能的影响。研究结果表明:随着碱炭比增大,活性炭材料的比表面积与总孔容、中孔孔容、微孔孔容先增大后减小,平均孔径不断增大。其中碱炭比值为6时的样品BAC6比表面积为3 166.5 m2/g,总孔容为2.023 cm3/g,平均孔径为2.555 nm,在有机电解液中以1 mA/cm2的电流密度充放电时,比电容高达172.9 F/g,电流密度增大50倍容量保持率为65.6%,显示出良好的功率特性。活性炭材料中存在一定比例的中孔不仅可以改善电极材料的功率特性,而且可以提高微孔的利用率。Activated carbon with distinct pore structure used for electric double-layer capacitor（EDLC） was prepared using bamboo char as raw material and KOH as activator by chemical activation.The effect of mass ratio of KOH/ carbon on the structure and properties of the activated carbon were investigated by means of SEM,nitrogen adsorption,galvanostatic charging/discharging,cyclic voltammetry and impedance spectroscopy.The results show that the BET surface area,the totle pore volume,mesoporosity volume and micropore volume of activated carbons increase firstly and decrease afterward with increasing ratio of KOH/ carbon,while the average pore size increases all the time.The specific surface area,total pore volume and average pore size of bamboo-based activated carbon at the mass ratio of KOH/carbon 6（BAC6） are 3 166.5 m2/g,2.023 cm3/g and 2.555 nm,respectively.Meanwhile BAC6 exhibites excellent specific capacitance over 172.9 F/g at 1 mA/cm2 and the capacitance maintenance achieves 65.6 % at 50 mA/cm2 in organic electrolyte.The high current charge/discharge performance is improved by a reasonable mesoporosity and somewhat wide pore size distribution.

关 键 词：竹基活性炭 KOH用量 孔结构 电化学性能 

分 类 号：TQ424[化学工程]