Facile synthesis of cuboid Ni-MOF for high-performance supercapacitors

• Published in: Journal of materials science 2018-05, Vol.53 (9), p.6807-6818
• Main Authors: Gao, Shuwen, Sui, Yanwei, Wei, Fuxiang, Qi, Jiqiu, Meng, Qingkun, He, Yezeng
• Format: Article
• Language: English
• Subjects: Activated carbon; Capacitance; Capacitors; Characterization and Evaluation of Materials; Charge transfer; Charge transport; Chemistry and Materials Science; Classical Mechanics; Crystallography and Scattering Methods; Electrode materials; Electrodes; Electrolytes; Energy Materials; Ion transport; Materials Science; Metal-organic frameworks; Nickel; Polymer Sciences; Solid Mechanics; Supercapacitors
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-018-2005-1

Metal–organic frameworks (MOF) used directly in supercapacitors have attracted much attention for their special porous structure and potential high performance. Here, the Ni-MOF is fabricated by one-step facile hydrothermal method with a modification of mixed solution with DMF and water instead of pure DMF. After characterization, the Ni-MOF exhibits loosely stacked layer-cuboid structure with abundant mesoporous, which is beneficial for the charge transfer and ion transport for supercapacitors. In the three-electrode system, this Ni-MOF serving as working electrode shows remarkable specific capacitance of 804 Fg −1 at 1 Ag −1 , excellent rate capacitance of 534 Fg −1 at 10 Ag −1 , and with 302 Fg −1 retention after 5000 cycles, when measured in 2 M KOH electrolyte solution. To make a further research into the practical utility of the Ni-MOF, the Ni-MOF//AC asymmetrical supercapacitor device is assembled with the Ni-MOF and active carbon acted as positive and negative electrode materials, respectively. This device exhibits high specific energy of 31.5 Wh kg −1 , at specific power of 800 W kg −1 . All these results demonstrate that this Ni-MOF is a kind of promising electrode material for high-performance supercapacitors.