High color purity blue phosphorescent organic lighting emitting devices

Abstract

The bottom-emitting microcavity organic lighting device (OLED) employs a structure of glass/AL(15nm)/MoO3(xnm)/ NPD (40nm)/mCP: FIrpic(30nm, 7%)/ Bphen (40nm)/ LiF(1nm)/ A l (150nm). The blue electrophosphorescence using exothermic energy transfer from a host consisting of N, N'-dcarbazolyl-3,5-benzene (mCP) to the phosphorescent iridium complex iridium(III) bis [(4, 6-difluorophenyl)-pyridinato-N, C2']picolinate (FIrpic), using MoO3 and LiF as efficient hole and electron injection layers, respectively. The cavity structure consists of the highly reflective Al cathode and the semitransparent Al anode. The emission spectrum of the microcavity OLED is centered at 468nm with a full width at half maximum (FWHM) of 22 nm, and CIE color coordinates are x=0.15 and y=0.13. It's indicated that microcavity effect can modulated and narrowed the spectrum.