Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Screens set to go green: Electronic screens based on new energy-efficient technology could become more affordable thanks to the substitution of expensive metal components with copper ones

Figure 1: The molecular structure of the bulky organic ligand that turns copper (green) into an efficient light emitter (yellow, phosphorus; red, bromine).

© 2011 Masahisa Osawa
Figure 1: The molecular structure of the bulky organic ligand that turns copper (green) into an efficient light emitter (yellow, phosphorus; red, bromine).

© 2011 Masahisa Osawa

Abstract:
Fitting the screens of electronic devices, such as televisions and smartphones, with a new display technology called ‘organic light-emitting diodes' (OLEDs) will reduce their energy consumption, but such screens currently require rare and expensive metal components. Now, Masahisa Osawa and his colleagues at the RIKEN Innovation Center in Wako, along with researchers from electronics company Canon, have found a way to replace these costly metals with copper1.

Screens set to go green: Electronic screens based on new energy-efficient technology could become more affordable thanks to the substitution of expensive metal components with copper ones

Japan | Posted on August 26th, 2011

In addition to offering significant energy savings over conventional LCD-based displays, OLED screens improve picture quality by producing richer blacks; they also offer a wider viewing angle. In an LCD screen, each pixel is effectively a little filter, selectively blocking light produced by a large backlight. In an OLED screen, however, each pixel is a tiny light emitter such that no backlight is needed. This means that pixels in dark areas of the image consume no power, reducing energy use.

To maximize the energy-saving benefit, screen makers select OLED materials that most efficiently convert electrical current into light, a property known as high external quantum efficiency (EQE). Some of the best materials are phosphorescent metal complexes, but these are typically composed of rare and expensive metals such as iridium.

Copper complexes have long been known as potential alternatives, and would cost 1/2,000th that of iridium phosphors, according to Osawa. Until the work of Osawa and his colleagues, however, these copper complexes had a low EQE. Such complexes can be readily excited into a high-energy state, but they tend to physically distort, which dissipates their extra energy rather than emitting it as light.

The researchers resolved this problem by altering the molecular environment in which the copper sits. They wrapped each copper ion inside a newly designed bulky organic ligand. They then conducted X-ray diffraction studies, which revealed that the ligand had forced the copper to become three-coordinate—it had formed three bonds to the ligand, rather than the usual four (Fig. 1).

Osawa and colleagues also demonstrated that the EQE of their green-light-emitting copper complex increased dramatically and matched that of iridium complexes. "The three-coordinate structure is a crucial factor for high EQE, because it hardly distorts in the excited state," Osawa explains.

The team's next step will be to deploy the complex in a working device. Copper might not be limited to producing green light, Osawa adds. "Our goal is to make red-, green-, and blue-colored phosphorescent three-coordinate copper materials."

The corresponding author for this highlight is based at the Luminescent Materials Laboratory, RIKEN Research Cluster for Innovation

####

About Riken Research
RIKEN is one of Japan’s largest research organizations, with more than 3,000 scientists involved in leading research in centers and institutes across Japan and around the world.

For more information, please click here

Copyright © Riken Research

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Laboratories

Scientists take key step toward custom-made nanoscale chemical factories: Berkeley Lab researchers part of team that creates new function in tiny protein shell structures February 6th, 2016

News and information

Scientists take key step toward custom-made nanoscale chemical factories: Berkeley Lab researchers part of team that creates new function in tiny protein shell structures February 6th, 2016

Discovery of the specific properties of graphite-based carbon materials February 6th, 2016

Hepatitis virus-like particles as potential cancer treatment February 5th, 2016

Organic crystals allow creating flexible electronic devices: The researchers from the Faculty of Physics of the Moscow State University have grown organic crystals that allow creating flexible electronic devices February 5th, 2016

Researchers discover new phase of boron nitride and a new way to create pure c-BN February 5th, 2016

Display technology/LEDs/SS Lighting/OLEDs

Organic crystals allow creating flexible electronic devices: The researchers from the Faculty of Physics of the Moscow State University have grown organic crystals that allow creating flexible electronic devices February 5th, 2016

Researchers discover new phase of boron nitride and a new way to create pure c-BN February 5th, 2016

Discoveries

Scientists take key step toward custom-made nanoscale chemical factories: Berkeley Lab researchers part of team that creates new function in tiny protein shell structures February 6th, 2016

Discovery of the specific properties of graphite-based carbon materials February 6th, 2016

Study reveals how herpes virus tricks the immune system February 5th, 2016

Hepatitis virus-like particles as potential cancer treatment February 5th, 2016

Announcements

Scientists take key step toward custom-made nanoscale chemical factories: Berkeley Lab researchers part of team that creates new function in tiny protein shell structures February 6th, 2016

Discovery of the specific properties of graphite-based carbon materials February 6th, 2016

Study reveals how herpes virus tricks the immune system February 5th, 2016

Hepatitis virus-like particles as potential cancer treatment February 5th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic