S-Space College of Engineering/Engineering Practice School (공과대학/대학원) Dept. of Material Science and Engineering (재료공학부) Journal Papers (저널논문_재료공학부)
A highly efficient wide-band-gap host material for blue electrophosphorescent light-emitting devices
- Whang, Dong Ryeol; You, Youngmin; Kim, Se Hun; Jeong, Won-Ik; Park, Young-Seo; Kim, Jang-Joo; Park, Soo Young
- Issue Date
- American Institute of Physics
- Appl. Phys. Lett. 91, 233501 (2007)
- We report on an efficient wide-band-gap host material for blue electrophosphorescence devices, namely, 1,2-trans-di-9-carbazolylcyclobutane (DCz). Photophysical studies show that lower-energy excimer formation between the carbazole units can be efficiently suppressed in a DCz film, thus maintaining its high triplet-state energy and inducing an exothermic energy transfer from DCz to iridium(III)bis[(4,6-difluorophenyl)-pyridinato-N,C2]picolinate (FIrpic). Electrophosphorescent devices comprising a FIrpic:DCz emitting layer exhibit a superior performance with a maximum external quantum efficiency of 9.8%, a maximum luminance efficiency of 21.5 cd/A, and a maximum power efficiency of 15.0 lm/W at 0.01 mA/cm2.
- 0003-6951 (print)