Degradation mechanism study and electron scattering device structure for long lifetime in blue phosphorescent organic light-emitting diodes

作者：Song Wook; Kim Taekyung; Lee Yoonkyoo; Lee Jun Yeob

来源：Organic Electronics, 2017, 43: 82-86.

DOI：10.1016/j.orgel.2017.01.016

• Lifetime
• Triplet-polaron annihilation
• Degradation
• Blue emitter
• Electron scattering

Degradation of Ir based blue phosphorescent emitters was analyzed from the viewpoint of triplet-polaron annihilation (TPA) of the emitters. Two different classes of Ir emitters, F substituted phenyl pyridine type Ir emitter and F substituted phenylimidazole type Ir emitter, were compared as the blue emitters. Aging test of singlet carrier devices of the Ir emitters under polaron, exciton, and exciton-polaron revealed that the phenylimidazole type Ir emitter was relatively more resistant to the TPA degradation than the phenylpyridine type Ir emitter and extended the lifetime of blue phosphorescent organic light-emitting diodes. In addition, the lifetime and degradation of the short-living blue phosphorescent devices were improved by the host material suppressing the TPA under negative polaron using an electron scattering emitting layer structure.

• 出版日期2017-4