Electroluminescent device with red triplet emitter

摘要

An organic light-emitting device contains a cathode, an anode, and having located there-between a light-emitting layer, comprising: a) a host material including an organometallic compound represented by Formula (1): wherein: R¹ through R⁶ each independently represent hydrogen or a substituent group, and L represents a substituent; and b) at least one phosphorescent light-emitting compound, with a triplet energy less than or equal to the triplet energy of the host material. The device provides an improved combination of low voltage and luminance efficiency.