Solution processed single-emission layer white polymer light-emitting diodes with high color quality and high performance from a poly(N-vinyl)carbazole host.

Low cost and high performance white polymer light-emitting diodes (PLEDs) are very important as solid-state lighting sources. In this research three commercially available phosphors were carefully chosen, bis[2-(4,6-difluorophenyl)pyridinato-N,C(2)](picolinate)iridium(III) (FIrpic), bis[2-(2-pyridinyl-N)phenyl-C](2,4-pentanedionato-O(2),O(4))iridium(III) [Ir(ppy)2(acac)], and bis(2-phenyl-benzothiazole-C(2),N)(acetylacetonate)iridium(III) [Ir(bt)2(acac)], plus a home-made red phosphor of tris[1-(2,6-dimethylphenoxy)-4-(4-chlorophenyl)phthalazine]iridium(III) [Ir(MPCPPZ)3], and their photophysical and morphological properties were systematically studied as well as their applications in single-emission layer white PLEDs comprising poly(N-vinylcarbazole) as host. Additionally, the electrochemical properties and energy level alignment, possible energy transfer process, and thin-film morphology were also addressed.