预炭化对KOH活化石油焦的结构及电容性能的影响  

Effects of Precarbonization on Structure and Capacitive Behavior of Petroleum Coke Activated by KOH

作　　者：时志强[1] 赵朔[1] 陈明鸣[1] 王妹先[1] 王成扬[1] 

机构地区：[1]天津大学化工学院绿色合成与转化教育部重点实验室,天津300072

出　　处：《无机材料学报》2008年第4期799-804,共6页Journal of Inorganic Materials

基　　金：天津市应用基础及前沿技术研究计划重点项目(08JCZDJC17000)

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N_2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:通过调整前驱体的预炭化温度,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.The carbon electrode materials for electrochemical capacitors were prepared from petroleum coke precursor carbonized at different temperatures followed by KOH activation. The precursors and activated products were characterized by XRD, TEM and N2 adsorption techniques. The capacitive behavior of activated petroleum coke was also examined. Results show that crystallite structure and pore structure of activated petroleum cokes can be controlled by adjusting the precarbonization temperature, and so non-crystalline high surface area activated carbons and crystalline low surface area novel activated carbons which consist of large amount of graphite-like crystallite are obtained. The energy storage for the low surface area activated carbon depends on the intercalation of electrolyte ions into graphite-like crystallite layers during the charge process. The surface specific capacitance of the low surface area activated carbon is over ten times of that for high surface activated carbon, and the low surface area activated carbon has a higher volumetric specific capacitance.

关 键 词：电化学电容器 类石墨微晶 电化学活化 比电容 

分 类 号：TM242[一般工业技术—材料科学与工程] TM53[电气工程—电工理论与新技术]