Negative Polaron‐Stabilizing Host for Improved Operational Lifetime in Blue Phosphorescent Organic Light‐Emitting Diodes


Sung Yong Byeon, Si Hyun Han, Jun Yeob Lee

Negative polaron stabilizing host materials for blue phosphorescence organic light‐emitting diodes are synthesized by modifying carbazolylcarbazole with dibenzothiophene or 9‐phenylcarbazole. The host materials show high triplet energy above 2.95 eV and work as hole transport type hosts. Operational lifetime analysis of the blue devices with the two hosts demonstrates that the dibenzothiophene modified carbazolylcarbazole host functions better than the 9‐phenylcarbazole modified carbazolylcarbazole host. Improved negative polaron stability from bond dissociation energy calculation and single carrier aging test results is the main factor for the lifetime extension in the dibenzothiophene modified carbazolylcarbazole host based blue phosphorescent organic light‐emitting diodes.

The MS analysis was carried out using Advion Expression® CMS.