Daniel David Lecloux

Highly efficient electroluminescent materials based on fluorinated organometallic iridium compounds

We report a class of highly efficient electroluminescent materials based on fluorinated iridium compounds. Using aluminum as the cathode, a device, using fac-tris[5-fluoro-2(5-trifluoromethyl-2-pyridinyl)phenyl-C,N]iridium (Ir-2h) as the luminescent layer, displayed intense electroluminescence at 525 nm with an efficiency of 20 cd/A and a maximum radiance of 4800 cd/m2. Differing from the previously reported Ir(ppy)3, Ir-2h can be used in the undiluted form without the use of a charge-transporting host. This indicates that Ir-2h by itself has good enough charge-transporting properties. Photoluminescence studies at room temperature and 77 K revealed that electroluminescence originates from the metal-to-ligand charge transfer state with a quantum yield of 0.56 for Ir-2h and 0.5 for Ir(ppy)3 in toluene at room temperature. In the thin-film form, photoluminescence quantum yield of Ir-2h is a factor of 10 greater than that of Ir(ppy)3 due to the larger self-quenching effect of Ir(ppy)3.

New, efficient electroluminescent materials based onorganometallic Ir complexes

Reaction of IrCl3 with fluorinated 2-arylpyridines in the presence of AgO2CCF3 affords fac-tris-cyclometalated arylpyridine Ir complexes exhibiting excellent processing and electroluminescent properties which can be fine-tuned via systematic control of the nature and position of the substituents on the aromatic rings.

OLED technology scalable for television: Solution process delivers printed lifetime

DuPont recently announced the achievement of record performance in printed organic light emitting diode (OLED) displays, sufficient to enable future adoption of OLED television. Printed devices have reliably achieved T50 luminance lifetimes of 29,000 (red), 110,000 (green) and 34,000 hours (blue) at typical television brightness.