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A capacitor is an electric energy storage device, often constructed with two layers of conducting foil separated by a paper-thin layer of insulator. The capacity is proportional to the area A and inversely proportional to the insulator thickness t, C~A/t. A supercapacitor has a atomic scale insulator thickness given by the solvation layer surrounding an ion in an electrolyte, and a large surface area. Supercapacitor values of 1-1000 F are now available commercially and approach the energy density of batteries while offering fast charge and discharge rates (high power density). For an introduction to graphene based supercapacitors, see http://vimeo.com/51873011. -duncan
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Construct a supercapacitor.

Graphene Micro-Supercapacitors

Fabrication of LSG-MSC

Project Overview

A capacitor is an electric energy storage device, often constructed with two layers of conducting foil separated by a paper-thin layer of insulator. The capacity is proportional to the area A and inversely proportional to the insulator thickness t, C~A/t. A supercapacitor has a atomic scale insulator thickness given by the solvation layer surrounding an ion in an electrolyte, and a large surface area. Supercapacitor values of 1-1000 F are now available commercially and approach the energy density of batteries while offering fast charge and discharge rates (high power density). For an introduction to graphene based supercapacitors, see http://vimeo.com/51873011. -duncan

Project Goals

Construct a supercapacitor.

Relevant Publications

  • Scalable fabrication of high-power graphene micro-supercapacitors for flexible and on-chip energy storage

    • Maher F. El-Kady & Richard B. Kaner

      • El-Kady and Kaner demonstrate a scalable fabrication of graphene micro-supercapacitors over large areas by direct laser writing on graphite oxide films. More than 100 micro-supercapacitors can be produced on a single disc in 30 min or less. The devices are built on flexible substrates for flexible electronics and on-chip uses. Remarkably, miniaturizing the devices to the microscale results in enhanced charge-storage capacity and rate capability. These microsupercapacitors demonstrate a power density of ~200 W cm-3, which is among the highest values achieved for any supercapacitor.

    Preparation of Graphitic Oxide

    • William S. Hummers & Richard E. Offema

      • The conventional method for the preparation of graphitic oxide is time consuming and hazardous. Hummers and Offema have developed a rapid, relatively safe method for preparing graphitic oxide from graphite in what is essentially an anhydrous mixture of sulfuric acid, sodium nitrate and potassium permanganate.

    Layer-by-Layer Assembly of Ultrathin Composite Films from Micron-Sized Graphite Oxide Sheets and Polycations

    • Nina I. Kovtyukhova et al.
      • For the synthesis of graphitic oxide, El-Kady and Kaner used a modified Hummers' method developed by Nina I. Kovtyukhova et al.

None: Graphene Micro-Supercapacitors (last edited 2013-10-28 21:42:06 by DuncanCarlsmith)