New host material for high-performance blue phosphorescent organic electroluminescent devices.

A new carbazole derivative with two carbazole moieties on the C3 and C6 positions of carbazole and triphenylsilane directly linked to the N of carbazole is successfully used as a highly efficient blue phosphorescent host in an organic light-emitting diode (PhOLED). The blue PhOLED, with this new host, gives an extremely high external quantum efficiency.