Zhang Jiahao, Wang Zizhun, Deng Ting, Zhang Wei
State Key Laboratory of Automotive Simulation and Control, School of Materials Science and Engineering, Electron Microscopy Center, and International Center of Future Science, Jilin University, Changchun 130012, People's Republic of China.
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China.
Nanotechnology. 2021 May 7;32(19):195404. doi: 10.1088/1361-6528/abdf8e.
Metal organic frameworks (MOFs) are expected to be promising pseudocapacitve materials because of their potential redox sites and porous structures. Nevertheless, the conductivity inferiority of MOF strongly decreases their structural advantages, therefore resulting in unsatisfying electrochemical performance. Herein, we propose an efficient strategy to enhance conductivity and thus electrochemical properties, in Ni(OH) is electrochemically deposited on carbon nanowalls as the precursor for oriented MOF. The synthesized vertically oriented MOF sheets show an almost triple high capacitance of 677 F g than MOF powder of 239 F g at the current density of 2 A g. Correspondingly, an asymmetric supercapacitor is fabricated, which can deliver a maximum energy density of 20.7 Wh kg and a maximum power density of 23 200 W kg. These promising results indicate that modulating the conductivity of MOF is the key step to pursuit upgrading electrochemical performance.
金属有机框架材料（MOFs）因其潜在的氧化还原位点和多孔结构而有望成为有前景的赝电容材料。然而，MOF的导电性较差严重削弱了其结构优势，从而导致电化学性能不尽人意。在此，我们提出一种有效策略来提高导电性，进而改善电化学性能，即将Ni(OH)电化学沉积在碳纳米壁上作为定向MOF的前驱体。合成的垂直取向MOF片在2 A g的电流密度下显示出677 F g的电容，几乎是239 F g的MOF粉末电容的三倍。相应地，制备了一种不对称超级电容器，其可提供20.7 Wh kg的最大能量密度和23200 W kg的最大功率密度。这些令人鼓舞的结果表明，调节MOF的导电性是追求提升电化学性能的关键步骤。
