Abstract
Todays, metal-organic frameworks (MOFs) and their derived structures have been extensively investigated as the novel electrode materials in energy storage area due to their stable porous architectures and exceptionally large specific surface area. In this study, bimetallic Ni,Zn-MOF is synthesized onto Ni foam via a novel indirect cathodic electrodeposition method for the first time. After that, the fabricated Ni,Zn-MOFs onto Ni foam was converted to corresponding bi-metal hydroxide@C/Ni foam through direct chemical treating with 6M KOH solution. The obtained Ni,Zn-MOFs/NF and Ni2 − xZnx (OH)2@C/NF electrodes are characterized through XRD, FT-IR, FE-SEM and EDS analyses. These analyses results confirmed deposition of well-defined crystalline porous sheet-like structures of Ni3 − xZnx(BTC)2 deposited onto Ni foam, where the hydroxide@C electrode was also exhibited similar morphology. As the binder-free electrode, the as-prepared Ni,Zn-MOF@Ni foam exhibited the superior storage capacities of 356.1 mAh g− 1 and 255.5 mAh g− 1 as well as good cycling stabilities of 94.2 % and 84.5 % after 6000 consecutive charge/discharge cycles at the current densities of 5 and 15 A g− 1, respectively. On the other hand, Ni,Zn-MOF derived hydroide@C/Ni foam presented the superior capacities of 545 mAh g− 1 and 406 mAh g− 1 as well as proper cycle lifes of 91.8 % and 78.3 % after 6000 cycling at the applied loads of 5 and 15 A g− 1, respectively. Based on these findings, both of these fabricated battery-type electrodes are introduced as the promising candidates for use in energy storage devices.
Interfacial growth of free-standing PANI films: toward high-performance all-polymer supercapacitors