Deep blue phosphorescent organic light-emitting diodes using a Si based wide bandgap host and an Ir dopant with electron withdrawing substituents

A deep blue phosphorescent organic light-emitting diode was developed using a diphenyldi(4-(9-carbazoly) lphenyl)silane(SiCa) host material and a tris((3,5-difluoro-4-cyanophenyl)pyridine) iridium(FCNlr) dopant material. Triplet bandgap of the SiCa was 3.0 eV, while triplet bandgap of the FCNlr was 2.8 eV. Light-emitting performances of blue devices were investigated by changing doping concentration of the FCNlr and a pure blue emission with a color coordinate of (0.15, 0.19) could be obtained. (C) 2008 Elsevier B.V. All rights reserved.