Univ.
of Michigan engineering
researchers have designed an efficient fluorescent blue OLED, or organic light
emitting diode.
OLEDs are the next generation display technology. They are
already used in televisions, cell phones and computers, and they are candidates
for a vast array of light sources from advertising billboards to indoor and
outdoor illumination. Fluorescent OLEDs are typically less efficient at
emitting light per unit area than their phosphorescent counterparts.
That may be changing, according to new findings by professor
John Kieffer and graduate student Changgua Zhen of the Department of Materials
Science and Engineering. They released findings in Advanced Functional Materials that shattered previous records.
Traditionally, the ceiling for the efficiency of fluorescent OLEDs was believed
to be 5%. Now, Kieffer and his collaborators have produced fluorescent OLEDs
with close to 10% efficiency.
“Our results clearly indicate that fluorescent material
have a bright future for highly efficient and stable OLEDs for flat-panel
display and lighting applications,” Kieffer said.
This was accomplished by redesigning a material being
utilized by U-M collaborators in Singapore using computer
simulations.
“With the material, they had some positive
results,” Kieffer said. “We took those molecules and started to
reconfigure them in a computer model, adding different functional groups in a
systematic way. We identified the mechanisms that control the performance of
OLEDs, and by applying the fundamental understanding so obtained we improved
the materials characteristics. Our research demonstrated the importance of
simulation-based predictive design.”
The paper is called: “Achieving Highly Efficient
Fluorescent Blue Organic Light-Emitting Diodes Through Optimizing Molecular
Structures and Device Configuration”
The research was funded by the Michigan Memorial Phoenix
Energy Institute (MMPEI) and the Institute
of Materials Research and
Engineering (IMRE).
