摘要
本文通过优化碳气凝胶前驱体的配比以及采用3种活化工艺,包括CO_2物理活化、KOH化学湿法活化以及CO_2、KOH两步活化工艺,研究了制备高比表面积碳气凝胶的工艺参数,并对碳气凝胶的微观结构和相应的电化学特性进行了表征和分析。结果表明,间苯二酚与碳酸钠的摩尔比(R/C)为1500时,获得的碳气凝胶比表面积达到820 m^2/g,比电容量为151 F/g;经物理活化、化学湿法活化以及两步活化工艺后获得的活化碳气凝胶的比表面积分别为1589 m^2/g、1480 m^2/g、2119 m^2/g,比电容量分别为181 F/g、229 F/g、259 F/g。相比之下两步活化法不但提升了碳气凝胶的比表面积,而且制备的碳气凝胶材料表现出更良好的电化学性能。
The carbon aerogels are prepared by using resorcinol and formaldehyde as precursor,Na2CO3 as catalyst and water as solvent with sol-gel technology,following drying and carbonization at high temperature.The optimized parameters of the preparation of high specific surface area carbon aerogels in this paper have been investigated by adjusting the ratios of precursors and applying three activated processes：carbon dioxide physical activation process,potassium hydroxide wet chemical activation process,and two steps activation process of carbon dioxide and potassium hydroxide for the application of carbon aerogels in supercapacitors.Moreover the microstructure of carbon aerogels and their corresponding electrochemical properties have been characterized and analyzed.The results indicated that the original specific surface area and specific capacitance of the unactivated carbon aerogel are 820 m^2/g and 151 F/g respectively as the molar ratio of resorcinol and sodium carbonate（R/C） is 1500.After the carbon dioxide physical activation process,potassium hydroxide wet chemical activation process,and two steps activation process respectively,their specific surface areas increased to 1589 m^2/g,1480 m^2/g and 2119 m^2/g and the specific capacitances of the samples reached to 181 F/g,229 F/g and 259 F/g.By contrast,the two-step activation not only enhance the specific surface area,but also form a hierarchically porous structures of the carbon aerogels,which is advantageous to be applied in the supercapacitors.
出处
《储能科学与技术》
CAS
2016年第6期828-833,共6页
Energy Storage Science and Technology
基金
上海航天科技创新基金(SAST201469、SAST201272)
国家自然科学基金(51072137)项目
关键词
碳气凝胶
电化学超级电容器
活化工艺
比表面积
carbon aerogels
electrochemical supercapacitors
activated process
specific surface area
