High-efficiency organic electrophophorescent devices through balance of charge injection

Balancing the charge injection plays an important role not only in fluorescence-based organic light-emitting devices, but also in the performance of the recently introduced organic electrophosphorescent devices. By achieving a better balance in the injected charges, it is possible to fabricate devices based on the pure red emitter 2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23H-porphine, PtOEP, with external quantum efficiency close to 9%. (C) 2002 American Institute of Physics.