Dilute NiO/carbon nanofiber composites derived from metal organic framework fibers as electrode materials for supercapacitors

Abstract

A new type of carbon nanofiber (CNF) dominated electrode materials decorated with dilute NiO particles (NiO/CNF) has been in situ fabricated by direct pyrolysis of Ni, Zn-containing metal organic framework fibers, which are skillfully constructed by assembling different proportional NiCl 2 •6H 2 O and Zn(Ac) 2 •2H 2 O with trimesic acid in the presence of N,N-dimethylformamide. With elegant combination of advantages of CNF and evenly dispersed NiO particles, as well as successful modulation of conductivity and porosity of final composites, our NiO/CNF composites display well-defined capacitive features. A high capacitance of 14926 F g-1 was obtained in 6 M KOH electrolyte when the contribution from 0.43 wt% NiO was considered alone, contributing to over 35% of the total capacitance (234 F g-1). This significantly exceeds its theoretical specific capacitance of 2584 F g-1. It has been established from the Ragone plot that a largest energy density of 33.4 Wh kg-1 was obtained at the current density of 0.25 A g-1. Furthermore, such composite electrode materials show good rate capability and outstanding cycling stability up to 5000 times (only 10% loss). The present study provides a brand-new approach to design a high capacitance and stable supercapacitor electrode and the concept is extendable to other composite materials.

Synthesis of Ag/NiO Honeycomb Structured Nanoarrays as the Electrode Material for High Performance Asymmetric Supercapacitor Devices

“…Y. Yang et al . 23 produced dilute NiO/carbon nanofiber composites synthesized from the metal-organic framework and reported a specific capacitance of 234 F g −1 at a scan rate of 1 mV s −1 . The present study achieved a 3.5 times higher specific capacitance at a higher applied current rate.…”

“…Y. Yang et al . 23 reported dilute NiO/carbon nanofiber composites synthesized from the metal-organic framework. Dilute NiO/carbon nanofiber composites yielded 234 F g −1 at a scan rate of 1 mV s −1 .…”

Porous Fiber Processing and Manufacturing for Energy Storage Applications

“…Porous materials including nanoporous fibers have found various applications. One of the most important applications is for energy storage devices for example, capacitors [117][118][119][120][121][122][123][124][125][126][127][128][129][130][131] and rechargeable batteries [132][133][134][135][136][137]. Another important branch of applications is environment protection related.…”

“…The metal organic framework based templating approach can also be applied for the mesoporous carbon nanofiber (CNF) preparation through the complete removal of the sacrificial Zn element and incorporation of other elements to generate the required oxides during carbonization. For example, Ni [124], Fe and Ru [125] can be readily embedded into porous carbon nanofibers by adding the source agents in the precursor solution. As illustrated in Figure 17 [126], trimesic acid (H 3 BTC), RuCl 3 , FeCl 3 and Zn(Ac) 2 •2H 2 O were used to prepare the DMF based precursor solution for the Ru, Fe-containing zinc-trimesic acid metal organic framework fiber through the solvothermal reaction at 140 • C for 12 h. The obtained fiber was heat treated at 950 • C for 2 h in nitrogen atmosphere to yield the mesoporous carbon nanofiber.…”

Nitrogen‐ and carbon‐richNi2O3nanolayer shieldedNi3Celongated square bipyramidal‐like nanostructures for hybrid supercapacitors

“…As a solution, combining the above-mentioned materials with carbonaceous materials could be a prominent scheme for better energy storage performance and cycling stability. 19 Transitional metal carbides (TMCs), which are a combination of transition metals and carbon-related materials as defined by Gao et al, would be a good choice as a SC electrode material to improve the rate capability and cycling stability. 20 These TMCs possess superior mechanical, thermal, and chemical stabilities.…”