The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

Ultracapacitors: Why, How, and Where is the Technology

Nanoporous carbon (NPC) materials with high specific surface area have attracted considerable attention for electrochemical energy storage applications. In the present work, we have designed novel symmetric supercapacitors based on NPC by direct carbonization of Zn-based metal-organic frameworks (MOFs) without using an additional precursor. By controlling the reaction conditions in the present study, we synthesized NPC with two different particle sizes. The effects of particle size and mass loadings on supercapacitor performance have been carefully evaluated. Our NPC materials exhibit excellent electrochemical performance with a maximum specific capacitance of 251 F g-1 in 1 M H2SO4 electrolyte. The symmetric supercapacitor studies show that these efficient electrodes have good capacitance, high stability, and good rate capability.

Fabrication of symmetric supercapacitors based on MOF-derived nanoporous carbons

Graphene-based functional nanomaterials for biomedical and bioanalysis applications

SnO2/SnS2 nanocomposite anchored on nitrogen-doped RGO for improved photocatalytic reduction of aqueous Cr(VI)

Novel tetrahedral Ag3PO4@N-rGO for photocatalytic detoxification of sulfamethoxazole: Process optimization, transformation pathways and biotoxicity assessment

Enhanced capacitance properties of nitrogen doped reduced graphene oxide obtained by simultaneous reduction and nitrogen doping

Electrodeposited MnCO3 as a High Performance Electrode Material for Supercapacitor

Tuning the Capacitance Properties of Nanocrystalline MnCO3by the Effect of a Carbonizing Agent

Unveiling Mesoporous Graphitic Carbon Nitride as a High Performance Electrode Material for Supercapacitors

Tuning the chemical composition, textural and capacitance properties of mesoporous graphitic carbon nitride

Mustapha Balarabe Idris

Papers

Enhanced capacitance properties of nitrogen doped reduced graphene oxide obtained by simultaneous reduction and nitrogen doping

Electrodeposited MnCO3 as a High Performance Electrode Material for Supercapacitor

Tuning the Capacitance Properties of Nanocrystalline MnCO3by the Effect of a Carbonizing Agent

Unveiling Mesoporous Graphitic Carbon Nitride as a High Performance Electrode Material for Supercapacitors

Tuning the chemical composition, textural and capacitance properties of mesoporous graphitic carbon nitride