You all know that incandescent light bulbs are terribly inefficient, turning only 5% of the electricity they consume into light. Fluorescent lamps are better using up to 25% of its energy as light. And solid state lighting devices lose only 50% of the energy they received. But now, researchers at Arizona State University (ASU) claim they've developed organic lighting devices which are 100% efficient. The researchers think it's possible to produce these solid-state lighting devices based on OLED technology at low cost. If this is true, this would be of major benefit to the environment by conserving energy and natural resources.
These organic lighting devices have been developed by a team led by Ghassan Jabbour, professor at the ASU School of Materials, and Jian Li, an assistant professor in the same department. In addition, Jabbour is director of optoelectronics research and development at the Flexible Display Center at ASU.
What's particularly significant about the researchers' work is that their optimized device adopts an even simpler structure than any yet reported by other research groups. "There is no waste of electricity," Jabbour says. "All the current you are putting into the device is being used to produce light. It's the first time something like this has been demonstrated. Nobody else has shown a 100 percent internal quantum efficiency for lighting devices using a single molecular dopant to emit white light."
This research work has been published in Advanced Materials under the name "Excimer-Based White Phosphorescent Organic Light-Emitting Diodes with Nearly 100 % Internal Quantum Efficiency" (Volume 19, Issue 2, Pages 197-202, January 2007). Here are two links to the paper reference and a short comment about it. "By combining the monomer and excimer/aggregate emission of FPt, a white OLED can be obtained. Incorporating the novel host material 26mCPy and engineering the charge balance properties, Jabbour and co-workers used FPt to demonstrate, for the first time, nearly 100% internal quantum efficiency in white OLEDs."
As I've mentioned above, these lighting devices should be good for the environment. But this research work "also could accelerate advances in semiconductor technology materials through improvements in low-power organic thin-film transistors."
Sources: Arizona State University news release, April 12, 2007; and various websites
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