Highly efficient exciplex phosphorescence from organic light-emitting diodes

A highly efficient exciplex electrophosphorescent diode has been fabricated. The efficiency as high as 2.4% photon/carrier is achieved from the above double-layer structure using the organic materials as indicated in the figure. The emission originated from triplet exciplexes 3∣m-MTDATA:PtL2Cl〉∗ formed in the blend emitter m-MTDATA:BPT (1:1) 70 wt%: PtL2Cl 5 wt%:PC 25 wt% (70 nm) separated from the cathode by a 50 nm-thick BPT layer.