Multi-Resonant Indolo[3,2,1-]carbazole-Based Host for Blue Phosphorescent Organic Light-Emitting Diodes.

In organic light-emitting diodes, positive and negative charge carriers mostly migrate at different rates. This could result in excitons formed in the EML often migrating to the vicinity of the hole transport layer and the electron transport layer. To address this, it is important to design high-quality multi-resonance hosts that can balance the migration rate of carriers.