Zhang Cunrong, Zhang Qi, Zhang Kai, Xiao Zhenyu, Yang Yu, Wang Lei
Key Laboratory of Eco-chemical Engineering, Ministry of Education, Laboratory of Inorganic Synthesis and Applied Chemistry, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology Qingdao 266042 P. R. China
RSC Adv. 2018 May 15;8(32):17747-17753. doi: 10.1039/c8ra01002a. eCollection 2018 May 14.
Recently, various metal-organic framework (MOF)-based supercapacitors (SCs) have received much attention due to their porosity and well-defined structures. Yet poor conductivity and low capacitance in most MOF-based devices limit their wide application. As an electrode material, 2D MOFs exhibit a rapid electron transfer rate and high specific surface area due to their unique structures. In this work, a 2D layered Ni-MOF is synthesized through a simple solvothermal method and serves as an electrode material for SCs. Electrochemical studies show that the Ni-MOF exhibits low charge transfer resistance, excellent specific capacitance of 1668.7 F g at 2 A g and capacitance retention of 90.3% after 5000 cycles at 5 A g. Moreover, Ni-MOF//AC asymmetric SCs are assembled. The device exhibits high specific capacitance of 161 F g at 0.2 A g and the energy density reached 57.29 W h kg at a power density of 160 W kg. The high electrochemical performance can be ascribed to the inherent porosity of MOFs and the 2D layered structure.
近年来,各种基于金属有机框架(MOF)的超级电容器(SCs)因其孔隙率和明确的结构而备受关注。然而,大多数基于MOF的器件中导电性差和电容低限制了它们的广泛应用。作为一种电极材料,二维MOF由于其独特的结构而具有快速的电子转移速率和高比表面积。在这项工作中,通过简单的溶剂热法合成了二维层状Ni-MOF,并将其用作SCs的电极材料。电化学研究表明,Ni-MOF表现出低电荷转移电阻,在2 A g时具有1668.7 F g的优异比电容,在5 A g下循环5000次后电容保持率为90.3%。此外,组装了Ni-MOF//AC不对称SCs。该器件在0.2 A g时表现出161 F g的高比电容,在功率密度为160 W kg时能量密度达到57.29 W h kg。高电化学性能可归因于MOF的固有孔隙率和二维层状结构。