Intense Pulsed Light Annealing of Graphene Inks

NU 2015-104

 

Inventors

Ethan B. Secor

Bok Y. Ahn

Jennifer A. Lewis

Mark C. Hersam*

 

Short Description

Novel grapheme ink annealing technique compatible with various range of substrates offering rapid manufacturing of printed electronics

 

Abstract

Conductive inks represent a significant global market, and are critical for emerging applications in printed and flexible electronics. Graphene is a particularly attractive material for inks, offering electrical conductivity, chemical and environmental stability, and mechanical flexibility. Currently, high-performance graphene inks using polymer stabilizers such as ethyl cellulose require post-processing by thermal annealing, a slow process incompatible with many desirable substrates such as paper and plastic foils. Northwestern researchers, by using intense pulse light (IPL) annealing technique have invented a way to integrate graphene inks on thermally-sensitive substrates commonly used for printed electronics. This alternative annealing technique selectively heats the graphene patterns, decomposing the polymer stabilizer ethyl cellulose to offer rapid post-processing compatible with roll-to-roll manufacturing and a wide range of substrates, including polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), and glass. Combining this method with improved ink formulation, high-concentration graphene inks are demonstrated with metrics that are among the best for non-metal printed conductors.

 

Applications

  • Printed displays for consumer electronics
  • Radio frequency identification tags
  • Environmental and biomedical sensors
  • Intelligent packaging and textiles
  • Flexible energy harvesting/storage devices
  • Printed circuit boards

 

Advantages

  • Chemical and environmental stability
  • High electrical conductivity
  • Production from low-cost, abundant raw materials
  • Integration on a broad range of thermally-sensitive substrates
  • High-speed processing compatible with roll-to-roll manufacturing

 

Publication

Secor E, Ahn B, Gao T, Lewis J and Hersam M (2015) Rapid and Versatile Photonic Annealing of Graphene Inks for Flexible Printed Electronics. Advanced Materials. 27: 6683-8.

 

IP Status

Patent application has been filed

Patent Information: