Modification of Electronic Properties of Graphene-Based Materials for Improved Interfacial Capacitance for Electrical Energy Storage Applications

Physical Sciences : Materials and Compounds

Available for licensing

Inventors

  • Rodney Ruoff, Ph.D. , Mechanical Engineering
  • Li Li Zhang, Ph.D. , University of Texas at Austin
  • Meryl Stoller , Mechanical Engineering

Background/unmet need

The physical and chemical properties of carbon materials are critical to their performance as electrodes in supercapacitors. A large electrochemically accessible surface area, appropriate pore size and distribution, good interconnectivity of pores, continuous pathways for rapid ion transport, large electrical conductivity, and good wettability are all important factors for the electrode material of an electrical double layer (EDL) capacitor.

Ultra-thin, extremely high surface area carbon films have been identified as being promising for use as electrochemical dual layer capacitor electrodes. The development of higher surface area graphene materials alone will not be sufficient for continued increases in performance. The modification of the electronic properties of the materials will also be required.

Invention Description

This invention involves the modification of the electronic structure of graphene and activated graphenes by a dopant and the resulting enhancement of dual-layer capacitance. The inventors found that the area-normalized capacitance of activated graphene and lightly N-doped activated graphene with similar porous structure increased from 6 µF/cm2 to 22 µF/cm2 for 0 at% and 2.3 at% N-doping, respectively.

The increase in bulk capacitance with increasing N concentration and an increase in magnitude of quantum capacitance in N-doped monolayer graphene versus pristine monolayer graphene suggests that the increase in the electrochemical double-layer type of capacitance of many, if not all, N-doped carbon electrodes studied to date is primarily due to the modification of the electronic structure of the graphene by the N dopant.

Benefits/Advantages

  • Very high capacitance
  • High energy and power density
  • Longer lifetime

Features

    Modification of the electronic structure of graphene and activated graphenes by a dopant and the resulting enhancement of dual layer capacitance. 

Market potential/applications

Supercapacitor manufacturing companies for the applications of Li-ion battery, fuel cells, Photocatalysis, heterogeneous catalysis, and oxygen reduction reactions

Development Stage

Proof of concept

IP Status