Polymer and organic electronic device

摘要

An organic light-emitting device comprising an anode 203; a cathode 209; a first light-emitting layer 205 between the anode and the cathode; and a second light-emitting layer 207 between the first light-emitting layer and the cathode, where the first light-emitting layer comprises a hole-transporting material and a first phosphorescent material, the second light-emitting layer comprises a second phosphorescent material; and the lowest triplet excited state energy level of the hole-transporting material is lower than the lowest triplet excited state of the second phosphorescent material, and the same as or higher than the lowest triplet excited state energy level of the first phosphorescent material. The first phosphorescent material may emit red light while the second phosphorescent material may emit green and/or blue light, with the two emissions combined so that the device emits white light. This avoids quenching of phosphorescence and increases efficiency.