用于超级电容器电极材料的球形炭气凝胶  

Spherical carbon aerogels for supercapacitor electrodes

作　　者：蒋亚娴[1] 陈晓红[1] 宋怀河[1] 

机构地区：[1]北京化工大学材料科学与工程学院,北京100029

出　　处：《北京化工大学学报（自然科学版）》2007年第6期616-620,共5页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：北京市科技新星计划(2003B09);教育部留学回国人员启动基金(200405)

摘　　要：以2,4-二羟基苯甲酸(D)和甲醛(F)为原料,碳酸钾(C)为催化剂,采用溶胶-凝胶和乳液聚合的方法合成出球形炭气凝胶。利用SEM、粒径分布和BET测试法对样品的形貌和孔结构进行了分析。以制备的球形炭气凝胶作为超级电容器电极材料,利用恒流充放电研究其电容特性,考察了干燥方式和nD/nC对比电容的影响。结果表明,超临界干燥下,nD/nC为100的样品具有467m2/g的比表面积,孔径主要分布在2.5nm左右,在充放电电流密度为50mA/g时的比电容可达142F/g,该电极具有较好的循环性能和功率特性。Spherical carbon aerogels （SCA） have been synthesized by a sol-gel process involving inverse emulsion polymerization of formaldehyde with 2, 4-dihydroxybenzoic acid with the aid of K2CO3 as a catalyst. The morphology and surface properties of the materials were characterized by scanning electron microscopy and nitrogen adsorption measurements. The influence of varying synthesis conditions, such as the drying method （supercritical drying or ambient drying） and catalyst concentration, on the specific capacitance of SCA when used as an electrode in supercapacitors was investigated. It was found that SCA synthesized with a molar ratio of 2, 4-dihydroxybenzoic acid to K2CO3 （n D/n C） of 100 with supercritical drying had the highest BET surface area of about 467 m^2/g and a pore size centered at ＇2.5 nm. At a current load of 50mA/g, a specific capacitance of 142 F/g Was obtained using this sample. Supercapacitors based on SCA were found to exhibit good cycling stability and power density.

关 键 词：球形炭气凝胶 超级电容器 比电容 

分 类 号：TM53[电气工程—电器]