核桃壳基活性炭的制备及其在超级电容器中的应用  

Preparation of walnut shell-based activated carbon and its application in supercapacitor

作　　者：张静雪 梁晓怿[1] 贾倩 ZHANG Jing-xue;LIANG Xiao-yi;JIA Qian(School of Chemical Engineering,East China University of Science and Technology,Shanghai 200030,China)

机构地区：[1]华东理工大学化工学院

出　　处：《现代化工》2020年第1期180-184,共5页Modern Chemical Industry

摘　　要：以核桃壳为原料,在不同活化时间下用水蒸气活化法制备了3种具有不同比表面积的活性炭。利用SEM、FT-IR、XRD和康塔吸附仪探究活化时间对材料的表面形貌、物相结构和孔径分布的影响。并通过恒电流充放电法、循环伏安法等测试其电化学性能。3个样品均表现出优异的大倍率性能(最大电流密度为20.0 A/g)。结果表明,随着活化时间增加,样品的比表面积增大,比电容增大,但稳定性下降。活化时间为120 min时活性炭样品比表面积为1644 m^2/g,孔径分布合理;在有机电解液体系中最大比电容为83.8 F/g,最大能量密度为18.2 Wh/kg,该样品具有良好的稳定性和可逆性,最适合长期应用。Three kinds of activated carbon samples with different specific surface areas are prepared from walnut shell by using the steam activation method under different activation time.The influences of activation time on morphology,physical characters and pore structure parameters of the samples are studied by means of scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD)and N2 adsorption/desorption method.Electrochemical performances of the samples are evaluated through galvanostatic charge-discharge,cyclic voltammetry and so on.It is found that all three samples exhibit extraordinary rate performance under high current density(up to 20 A·g^-1).As the activation time prolongs,specific surface area and capacitance as well as energy density of the samples increase,however their stability decrease.The sample(AC120)prepared over an activation time of 120 minutes has a reasonable pore size distribution and a surface area of 1644 m^2·g^-1.In an organic electrolyte system,AC120 sample’s maximum specific capacitance and maximum energy density is 83.8 F·g^-1 and 18.2 Wh·kg^-1,respectively.AC120 also shows better performance in reversibility and stability,thus making it most suitable in long-term utilization.

关 键 词：核桃壳 活性炭 活化时间 超级电容器 电化学性能 

分 类 号：TM912.9[电气工程—电力电子与电力传动]