| 초록 |
In this work, dibenzothiophene derivatives were synthesized as hole transport type host materials for blue phosphorescent organic light-emitting diodes (OLEDs). The new dibenzothiophene based host materials showed planar core structure, triplet energy of higher than 2.8 eV, and excellent device performances as the host materials in blue phosphorescent OLEDs. The HOMO energy levels of host materials were -5.85 eV and -5.80 eV, while the LUMO energy levels of host materials were -2.09 eV and -2.26 eV, respectively. Maximum quantum efficiency of blue phosphorescent devices was 27.8% at a 10% doping concentration and the color coordinate of the device was (0.18, 0.38) at 1000 cd/m2. It was found that the dibenzothiophene based hole transport type host design was effective to improve the device performances of blue phosphorescent OLEDs. |
