Nano scientists to develop next-generation LEDs

Mar 19, 2007

Nanotechnology may unlock the secret for creating highly efficient next-generation LED lighting systems, and exploring its potential is the aim of several projects centered at Oak Ridge National Laboratory.

Seen everywhere today from traffic signals, taillights and cell phone displays to stadium JumboTrons, light emitting diodes fluoresce as electrical current passes through them. The most developed LED technology is based on crystals, typically made from indium gallium nitride. However, researchers at ORNL's Center for Nanophase Materials Sciences and the University of Tennessee are working to develop technology that will improve a new generation of LED devices composed of thin films of polymers or organic molecules.

These organic LEDs are designed to be formed into thin, flexible sheets that hold promise for a new generation of lighting fixtures and flexible electronics displays. Currently applications of organic LEDs, or OLEDs, are limited to small-screen devices such as cell phones, personal digital assistants and digital cameras; however it is hoped that someday large displays and lighting fixtures can be produced using low-cost manufacturing processes.

At ORNL, researchers are developing electrodes composed of carbon nanotubes and magnetic nanowires to enhance the light emission from polymer-based OLEDs. In early tests, carbon nanotubes improved the electroluminescence efficiency of polymer OLEDs by a factor of four and reduced the energy required to operate them. Magnetic nanowires and dots have been shown to help control the spin of electrons injected into the OLEDs to further improve the efficiency and reliability of the devices. A third aspect of the research focuses on creation and chemical processing of the nanotubes themselves. Researchers at ORNL use a technique called laser vaporization produces purer nanotubes with fewer defects than other fabrication techniques.

With assistance of a $600,000 grant from the Department of Energy's Office of Energy Efficiency and Renewable Energy, the ORNL/UT team hopes to merge the science and new materials research into a new technology for practical OLED devices that consumes less than half the power of today's technology and opens the door for their practical use in household lighting.

"The real, long-term solution to making a more efficient device may be found in nanoscience," said David Geohegan, an ORNL researcher who is leading the OLED effort. "Over the next year we hope to learn why nanomaterials enhance these devices. I think someday we will see OLEDs everywhere, from more durable touch-screen displays to electronic newspapers that we can roll up and carry easily to even larger wall displays for home entertainment or lighting."

Source: Oak Ridge National Laboratory

Explore further: Carbon nanoballs can greatly contribute to sustainable energy supply

add to favorites email to friend print save as pdf

Related Stories

TV makers out to ignite market with super high-def

Jan 06, 2015

After several years of sluggish sales, television manufacturers are pegging growth hopes on new technologies that deliver a more immersive and interactive experience and stunningly realistic image displays.

Montreal VR headset team turns to crowdfunding for Totem

Sep 18, 2014

A challenger in the virtual reality headset marketplace has launched a crowdfunding campaign to get the project off the ground. The headset is called Totem. The company behind Totem is Montreal-based Vrvana. ...

Recommended for you

Researchers use oxides to flip graphene conductivity

Jan 26, 2015

Graphene, a one-atom thick lattice of carbon atoms, is often touted as a revolutionary material that will take the place of silicon at the heart of electronics. The unmatched speed at which it can move electrons, ...

Researchers make magnetic graphene

Jan 26, 2015

Graphene, a one-atom thick sheet of carbon atoms arranged in a hexagonal lattice, has many desirable properties. Magnetism alas is not one of them. Magnetism can be induced in graphene by doping it with magnetic ...

The latest fashion: Graphene edges can be tailor-made

Jan 23, 2015

Theoretical physicists at Rice University are living on the edge as they study the astounding properties of graphene. In a new study, they figure out how researchers can fracture graphene nanoribbons to get ...

Nanotechnology changes behavior of materials

Jan 23, 2015

One of the reasons solar cells are not used more widely is cost—the materials used to make them most efficient are expensive. Engineers are exploring ways to print solar cells from inks, but the devices ...

Gold 'nano-drills'

Jan 22, 2015

Spherical gold particles are able to 'drill' a nano-diameter tunnel in ceramic material when heated. This is an easy and attractive way to equip chips with nanopores for DNA analysis, for example. Nanotechnologists ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.