KOH活化石油焦的结构及电容性能的影响论述.pdfVIP

第23卷第4期 2008年7月 无机材料学报 Journal of Inorganic Materi甜s 、，oL 23．No．4 Jul_．2008 文章编号：1000—324x(2008)0缸0799—06 预炭化对KoH活化石油焦的结构及电容性能的影响 时志强，赵朔，陈 (天津大学化工学院绿色合成与 明鸣，王妹先，王成扬 转化教育部重点实验室，天津300072) 摘要：以不同温度炭化的石油焦为原料、KOH为活化剂制备电化学电容器用炭电极材料．采用XRD、TEM 和Nz吸附法对前驱体及活化产物的结构进行了表征，并考察了样品的电化学性能．结果表明：通过调整前驱 体的顶炭化温度，可实现对石油焦基活性炭的微晶结构和孔结构的调控，分别制得无晶体特性的高比表面积活 性炭和由大量类石墨微晶构成的低比表面积活性炭．低表面积活性炭依靠充电过程中电解质离子嵌入类石墨微 晶层间而实现能量存储，具有比高比面积活性炭高10倍的面积比电容和更大的体积比电容． 关 键 词：电化学电容器；类石墨微晶；电化学活化；比电容 中图分类号：TM242，TM53 文献标识码：A E髓cts of Precarbonization on Structure and Capacitive Behavior of Petroleum Coke ActiVated by KoH SHI Zhi—Qiang，ZHAO Shuo，CHEN Ming-Ming，Ⅵ恰NG Mei—Xian，Ⅵ缓NG Chen乎Yang (Key Laboratory for Green Chemical Tbchnology of State Education Ministry，School of Chemical Engineering and Techn0109y，Tianjin university，Tianjin 300072，China) Abstract： The carbon electrode materials fbr electrochemical capacitorsⅥ伧re prepared ftom petro_ 1eum coke precursor carbonized at difrerent temperatures followed by KOH activation．The precursors and actiVated products、Ⅳere characterized by XRD，TEM and N2 adsorption techniques．The capacitive behavior of activated petroleum coke was also examined．f沁sults show that crystaUite structure and pore structure of actiVated petr01eum cokes can be controUed by adjusting the precarbonization temper— ature，and so non—crystaUine high surface area activated carbons and crystallinc low surface area novel actiVated carbons which consist of large amount of graphite—like crystaUite are obtained． The energy storage for the low surface area activated carbon depends on the intercalation of electrolyte ions into graphite—like crystaUite layers during the charge process． The surfAce specific capacitance of the 10w surface area activated carbon is oVer ten times of that for high sllrface actiⅦ吨ed carbon，and the low surface area actiVated carbon ha8 a higher Volumetric 8pecific capacitance． Key、7l，ords： electrochemical capacitors；graphite-1ike crystallite；electrochemical activation； speci丘c capacitan