title: Photophysical properties and OLED performance of light-emitting platinum(II) complexes.
abstract: The synthesis, photophysical properties and application as emitters in solution-processed multi-layer organic light-emitting diodes (OLEDs) of a series of blue-green to red light-emitting phosphorescent platinum(II) complexes are reported. These complexes consist of phenylisoquinoline, substituted phenylpyridines or tetrahydroquinolines as C^N cyclometalating ligands and dipivaloylmethane as an ancillary ligand. Depending on both the structure of the C^N cyclometalating ligands and the dopant concentration in the matrix, these platinum(II) complexes exhibit different aggregation tendencies. This property affects the photoluminescence spectra of the investigated compounds and colour-stability of the fabricated OLEDs. Using the blue-green to yellow-green emitting complexes, the best results were obtained with the 2-(4-trifluoromethylphenyl)-5,6,7,8-tetrahydroquinoline based platinum(II) complex. A maximum luminous efficiency of 4.88 cd A(-1) and a power efficiency of 4.65 lm W(-1), respectively, were achieved. Employing the red emitting phenylisoquinoline based complex as an emitter, colour-stable and efficient (4.71 cd A(-1), 5.12 lm W(-1)) devices were obtained.
authors.affiliation: Department of Chemistry, Universität zu Köln, Luxemburger Strasse 116, 50939 Köln, Germany.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kourkoulos
authors.forename: Cüneyt
authors.initials: C
authors.lastname: Karakus
authors.forename: Dirk
authors.initials: D
authors.lastname: Hertel
authors.forename: Ronald
authors.initials: R
authors.lastname: Alle
authors.forename: Sebastian
authors.initials: S
authors.lastname: Schmeding
authors.forename: Johanna
authors.initials: J
authors.lastname: Hummel
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Risch
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Holder
authors.forename: Klaus
authors.initials: K
authors.lastname: Meerholz
mesh_terms: D008027:Light; D015394:Molecular Structure; D009930:Organic Chemicals / Q000737:chemistry*; D009944:Organoplatinum Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D055668:Photochemical Processes
chemical_list: D009930:Organic Chemicals; D009944:Organoplatinum Compounds