High-efficiency blue light-emitting electrophosphorescent device with conjugated polymers as the host

Abstract
Highly efficient blue polymer phosphorescent organic light-emitting diode (PPHOLED)-containing iridium(III) bis (2,4-difluorophenyl-2-pyridine) (2-(4H-1, 2, 4-triazol-3-yl)pyridine) [Ir(PPF)2(PZ)] complex embedded into wide-gap poly (9,9′-alkyl-3, 6-silafluorene) (PSiFC6C6) has been fabricated. Despite the significant quenching of photophosphorescence emission of the iridium complexes by a PSiFC6C6 host polymer, organic light-emitting diodes containing Ir(PPF)2(PZ) doped into the polymer host PSiFC6C6 emit high-efficiency blue light peaked at 462nm. The maximal external quantum and luminance efficiencies were, respectively, 4.8% photons/electrons and 7.2cd∕A at 644cd∕m2 and with Commission Internationale de l’Eclairage coordinates of (0.15,0.26).