Blue light specials: New materials boost efficiency of blue OLEDs by 25 percent

Mar 22, 2009
New, more efficient host materials for the blue phosphorescent OLED (pictured) have been designed, developed and tested by Pacific Northwest National Laboratory scientists. By using new host materials, scientists have been able to improve the efficiency by at least 25 percent and have unlocked doors to developing much more efficient white OLEDs. Credit: Pacific Northwest National Laboratory

Lighting consumes one-fifth of the electricity generated in the United States. Solid-state lighting offers tremendous potential to improve the situation - once major research challenges are overcome.

The most promising technology is the organic light-emitting diode, or . These multi-layered devices produce light by running an electrical current through a specially engineered host material into which light-producing phosphorescent molecules are embedded or "doped." The white light envisioned for large-scale applications, such as rooms and buildings, consists of red, green and .

"The weakest link in OLED research is the absence of an efficient, long-lasting blue light to accompany the red and green," said Pacific Northwest National Laboratory scientist Asanga Padmaperuma. Development of better host to manage the flow of electricity through the device could help solve that problem.

Padmaperuma and his collegues have designed, synthesized and tested new materials that improve the of blue OLEDs by at least 25 percent.

On Sunday, March 22, PNNL scientists will discuss advancements in blue OLED research in two presentations and a poster session at the spring meeting of the American Chemical Society.

More information:

9:00 AM-11:40 AM, Room 155 D, Salt Place Convention Center
Novel ambipolar host and hole blocking material system for blue electrophosphorescent OLEDs

PNNL scientist Asanga Padmaperuma will present design strategies developed through computational and for engineering blue OLED materials.

2:00 PM-5:00 PM, Room 155 , Salt Place Convention Center
Synthesis and application of anchored 2,3,5-trifluoro-7,7,8,8-tetracyanoquinodimethane (F3TCNQ) as organic molecular dopants in OLEDs

PNNL scientist Phillip Koech will discuss a novel approach for controlling the doping concentration and of the dopant material.

8:00 PM-10:00 PM, Hall 5, Salt Place Convention Center
Design of multifunctional phosphorescent emitters with charge transport moieties

PNNL scientist Asanga Padmaperuma will present a poster highlighting the team's use of computational chemistry to develop multifunctional emitter materials for blue OLEDs.

Source: Pacific Northwest National Laboratory

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Soylent
5 / 5 (1) Mar 22, 2009
"Lighting consumes one-fifth of the electricity generated in the United States."

Not this BS again.

Only domestic users have incandecent light bulbs; that's only 10% of 25%, i.e. some 2-3% of electricity consumption in the US that is due to incandescent bulbs. The rest is various gas discharge lamps(HPS, LPS, metal halide...) and fluorescent lighting; there's very little potential to save energy with OLEDs here as it is already extremely efficient(e.g. HPS, LPS) or cheap and moderately efficient(fluorescents) or fit for a particular purpose(metal halide projector lamp, a very good point source).
StellarHelix
1 / 5 (1) Mar 23, 2009
Yes those types are efficient but efficiency is merely the measure of the amount of input power versus the amount of output. In the case of flourescent bulbs they require a ballast to kick the power up to start the process and the longer the tube the more power is needed. Add to the fact that the ballast suffers loses, which if I recall Magnetic Ballast have a general loss of 25% and electronic about 10%. This also holds true for mercury vapor lamps as well since they have to utilize a system to reach high frequency AC in order to, as they refer to it, stike an arc. LEDs do not require these mechanisms to operate so eliminating them would indeed mean a reduction in overall consumption. But maybe I am wrong.
Velanarris
not rated yet Mar 24, 2009
Yes those types are efficient but efficiency is merely the measure of the amount of input power versus the amount of output. In the case of flourescent bulbs they require a ballast to kick the power up to start the process and the longer the tube the more power is needed.
Yes but after that initial kick up the light is sustained at a far lower power consumption than an incandescent.
Add to the fact that the ballast suffers loses, which if I recall Magnetic Ballast have a general loss of 25% and electronic about 10%.
you're forgetting that incadescent lights spend the majority of their consumed energy generating heat, not light.

This also holds true for mercury vapor lamps as well since they have to utilize a system to reach high frequency AC in order to, as they refer to it, stike an arc.
This is also only used up front, the medium sustains performance at a far lower utilization after ignition.

LEDs do not require these mechanisms to operate so eliminating them would indeed mean a reduction in overall consumption. But maybe I am wrong.
You are wrong on this point. OLEDs still need a larger startup charge to function initially, sustaining the output takes far less.

Now if you wanted to argue for OLEDs you'd have to go with light output is far higher, presenting a greater quality of light and a more infinitely controllable spectrum. Then you'd be countered with a "who cares, white light incandescents are fine and cost 10,000% less."