Highly porous graphitic carbon and Ni₂P₂O₇for a high performance aqueous hybrid supercapacitor

Abstract

An aqueous Na-ion based hybrid capacitor has been successfully developed by highly porous graphitic carbon (HPGC) derived by waste writing paper and a new electrode material as negative and positive electrode, respectively. HPGC was prepared via hydrothermal carbonization and subsequent KOH activation of waste writing paper which showed highly porous stacked sheet like morphology with exceptionally high BET specific surface area (1254 m 2 g -1 ). HPGC exhibited typical electrical double layer capacitor (EDLC) behavior with a high specific capacitance of 384 F g -1 and good negative working potential (-1.0 V) in aqueous electrolyte. On the other hand, Ni2P2O7 was synthesized by simple co-precipitation technique and tested as cathode material which delivered a maximum specific capacitance of 1893 F g -1 at 2 A g -1 current density. The fabricated HPGC||Ni2P2O7 hybrid device displayed excellent cyclic stability up to 2000 cycles and delivered maximum energy density of 65 W h kg -1 at 800 W kg -1 power density in Na-ion based aqueous electrolyte.capacitive electrode by hemp carbonization and assembled

Electrospun Carbon Nanofibers Encapsulated with NiCoP: A Multifunctional Electrode for Supercapattery and Oxygen Reduction, Oxygen Evolution, and Hydrogen Evolution Reactions

“…The electrochemical reactions corresponding to the above events are as follows [16,36,37] x x ( ) ( ) ( )…”

“…[16,36,37] The collective CV curves of both negative and positive electrode are shown in Figure 7a to hone the working potential of the device. [16,36,37] The collective CV curves of both negative and positive electrode are shown in Figure 7a to hone the working potential of the device.…”

“…[16,17] Though contributing high power density is an important feature, a comparably low energy density with respect to batteries arises concern over the prospect of this dynamic device. The fast charging and discharging mechanism, large power density (10 kW kg −1 ), resilient cycling stability, and routine sustainable reliability of the supercapacitor draw a considerable magnitude of reputation over the other storage devices.…”

“…The fast charging and discharging mechanism, large power density (10 kW kg −1 ), resilient cycling stability, and routine sustainable reliability of the supercapacitor draw a considerable magnitude of reputation over the other storage devices. [16] Recently, Lei et al has reported a two-step approach for the preparation of polyacrylonitrile (PAN)/ligninbased carbon nanofibers by electrospinning and deposited the NiCo 2 O 4 on the surface of CNFs by a facile hydrothermal method. Many investigators working in this field are considering it as one of the resolute tasks to secure an enhanced energy density without troubling its charisma of delivering high power density.…”

Carbon‐Enriched Cobalt Phosphide with Assorted Nanostructure as a Multifunctional Electrode for Energy Conversion and Storage Devices

“…In view of sorting out this deprivation, the conventional supercapacitors are hybridized and familiarized as a flexible supercapattery. The supercapattery devices are designed by a non‐Faradaic electric double layer capacitor (EDLC)‐type electrode as an anode (negative electrode) and the Faradaic ‐type electrode as a cathode (positive electrode) . Here, the customary highly conductive carbon‐based materials such as activated carbon, 3D carbon nanostructures, porous carbon were used as EDLC electrodes to provide higher power density and the transition metal‐based materials were employed as a battery‐type electrode to ensure the enhanced energy density.…”