Polymer light-emitting diodes(PLEDs) containing Eu(DBM)3(Br DPPz)(DBM is dibenzoylmethane, and Br DPPz is 11- bromo-dipyrido[3,2-a:2′,3′-c]phenazine) doped in a blend of poly(9,9-dioctylfluorene)(PFO) and 2-tert-butylphenyl-5- biphenyl-1,3,4-oxadiazole(PBD) as the host matrix were reported. Eu(DBM)3(Br DPPz) exhibited high thermal stability and intense UV-Vis absorption. Narrow-bandwidth red emission at 612 nm with a full width at half-maximum(FWHM) of 14.0 nm was observed from Eu(DBM)3(Br DPPz) in these double-layered PLEDs at dopant concentrations from 1 wt% to 8 wt%. For the PLED containing 1 wt% Eu(DBM)3(Br DPPz), a maximum luminance of 829 cd/m2 at 153.5 m A/cm2, highest external quantum efficiency of 1.70% at 2.1 m A/cm2 and maximum luminance of 0.74 cd/A at 4.31 m A/cm2 were obtained.
Qunping FanYu LiuZhaoran HaoChun LiYafei WangHua TanWeiguo ZhuYong Cao
A novel red-emitting binuclear platinum complex （dfppy）zPtz（C^OXT）z was synthesized and characterized, in which dfppy represents 2-（4＇,6＇-difluorophenyl）pyridinato unit and CsOXT is abbreviated for 5-（4-octyloxyphenyl）-1,3,4-oxadiazole-2-thiol as a bridging ancillary ligand. Its photophysical, electrochemical and electroluminescent characteristics were primarily studied. The made single-emissive-layer （SEL） polymer light-emitting devices using （dfppy）2Ptz（CsOXT）2 as emitter exhibited a satu- rated red emission peaked at 620 nm. The best device performances were obtained in the device at 8 wt% dopant concentration, with a maximum external quantum efficiency of 8.4%, a current efficiency of 4.2 cd/A and brightness of 3228 cd/m~. This work provides an effective approach to obtain high-efficiency red emission through construction of new binuclear platinum complex and its doped SEL devices.
