P-171: Modulation of Dibenzothiophene and Carbazole Moieties in Host Material towards High Performance Blue Phosphorescent OLEDs

A new host material was synthesized for blue phosphorescent organic light emitting diodes (PHOLEDs) by modulating carbazolyl‐carbazole and dibenzothiophene groups. In particular, by comparing the characteristics of the two hosts with and without a biphenyl linker, we studied the effects of the biphenyl linker on photophysical properties and on the device performances of a blue emitting phosphorescent dopant. As a result, the newly synthesized host materials were functioned as high efficiency and long lifetime host materials in blue phosphorescent devices and they prolonged life span of the blue devices by 5 times compared to a common mCBP blue host.