Correlation of lifetime and recombination zone in green phosphorescent organic light-emitting diodes

Abstract

The lifetime of green phosphorescent organic light-emitting diodes was correlated with the charge leakage and recombination zone of the devices. The lifetime of green devices was decreased in the device with an electron leakage out of an emitting layer into a hole transport layer. In particular, the decrease in lifetime at high luminance was significant in the device with an electron leakage into the hole transport layer. In addition, the recombination zone of green devices was shifted from the hole transport layer side to the electron transport layer side during driving.