摘要
锂离子混合电容器兼具锂离子电池的高能量密度特性和超级电容器的高功率密度特性,是一种极具应用前景的新型储能器件.首先通过高温热解金属有机骨架(metal organic framework,MOF)前驱体的方法制备了MOF衍生的纳米多孔碳材料(碳化后的沸石咪唑酯骨架结构-8(carbonized zeolitic imidazolate framework-8,cZIF-8)),该材料具有高比表面积、较优异的孔隙率、良好的热稳定性和高导电性能.以电容型cZIF-8电极为正极,电池型钛酸锂(Li4Ti5O12,LTO)电极为负极,构筑一种新型的cZIF-8//LTO锂离子混合电容器.组装的设备最高能量密度达到44 W·h·kg-1,最高功率密度为5387 W·kg-1,其能量密度明显高于cZIF-8//cZIF-8超级电容器(16.6 W·h·kg-1).更为重要的是,cZIF-8//LTO锂离子混合电容器具有较优异的循环性能,在2 A·g-1的高电流密度下循环10000次后容量保留率高达85.4%.这种基于MOFs材料的锂离子混合电容器能使电化学储能器件在不降低功率性能的情况下有效提升能量密度.
Li-ion hybrid capacitors,which combine the high energy densities of Li-ion batteries and high power densities of super capacitors,are a new type of energy storage device with large application potentials.In this study,a porous carbon nanomaterial(carbonized zeolitic imidazolate framework-8(cZIF-8))derived from metal organic frameworks(MOFs)was synthesised by pyrolysis of a MOF precursor at a high temperature.This carbon material had a large specific surface area,excellent porosity,good thermal stability,and high conductivity.A new type of Li-ion hybrid capacitor(cZIF-8//lithium titanate(LTO))was constructed using a capacitor electrode based on cZIF-8 as a positive electrode and battery electrode based on LTO as a negative electrode.The assembled device had highest energy density of 44 W·h·kg-1 and power density of 5387 W·kg-1,significantly higher than that of a cZIF-8//cZIF-8 supercapacitor(16.6 W-h-kg-1).The Li-ion hybrid capacitor(cZIF-8//LTO)also exhibited a good cyclic performance(85.4%of the initial value after 10000 cycles)at a high current density of 2 A-g-1.This MOF-based Li-ion hybrid capacitor enables to effectively increase the energy density of the electrochemical energy storage device without reducing the power capability.
作者
姚伟伟
毛剑
张臣
李珍
吴明红
YAO Weiwei;MAO Jian;ZHANG Chen;LI Zhen;WU Minghong(School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200444,China)
出处
《上海大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第6期963-971,共9页
Journal of Shanghai University:Natural Science Edition
基金
国家自然科学基金资助项目(21471098)
长江学者和创新团队发展计划资助项目(IRT13078)。
关键词
纳米多孔碳
MOF衍生物
钛酸锂
锂离子混合电容器
porous carbon nanomaterial
metal organic framework(MOF)-derived material
lithium titanate(LTO)
Li-ion hybrid capacitor
