WiSys Technologies

Nanoscale Corona Discharge Electrode

WiSys Technology Number: T05014US
Patent Number: 7,504,628
Patent Issued Date: March 17, 2009 (PDF)
Status
Patented
Stage of Development:

OVERVIEW

Corona discharge is a process by which an electric field near a discharge electrode ionizes air to produce an electrical current between two electrodes. It has many industrial applications, including manufacturing ozone, scrubbing air particles in air-conditioning systems, removing unwanted volatile organics, and photocopying. But electrostatic photocopiers and other office machines that utilize corona discharge produce small amounts of ozone, which can be a health hazard. Current techniques to reduce ozone production and power consumption employ wire electrodes with radii as small as one micrometer; however, the ability to further decrease wire size is limited by practical considerations of wire strength and durability.


THE INVENTION

This invention describes the use of nanotubes and other nano-objects as corona discharge electrodes. A metal wire or plate, or other conductive substrate can be coated with nanostructures, such as carbon nanotubes, to produce a robust discharge electrode with a small radius of curvature. These novel corona ion sources provide high ion concentration and high charging efficiency with minimal ozone production.

APPLICATIONS

Useful in indoor air cleaners, photocopiers, printers, and nanofabricators


KEY BENEFITS

  • Extremely small (less than 100 nanometers) electrode radii
  • Low ozone production
  • Saves energy—can be operated with a lower corona discharge initiation voltage
  • Produces high ion concentration
  • High charging efficiency
  • Improved resistance to erosion
  • Simple to fabricate
  • Provides a flexible electrode design to fit particular applications
Inventor
Junhong Chen
Professor of Mechanical Engineering