Synthesis and electroluminescent properties of a carbozole-functionalized europium(III) complex

Efficient solution‐processed double‐layer red OLEDs based on a new europium complex with a carbazole group

“…There are two kinds of EL mechanisms for Eu(III) complex emission in OLEDs, i.e. Förster energy transfer and direct charge-trapping/ recombination mechanisms, and generally the latter is dominate (22)(23)(24)(25). No matter what kind of EL mechanism, if any to show only emission from this Eu(III) complex at a lower doping level, we can consider that this europium complex possessed a homogeneous distribution on the blend of PVK and PBD, being possibly resulted by a good film-formed property of EuL 3 (Phen) on the blend host (26,27).…”

Review on the Electroluminescence Study of Lanthanide Complexes

“…The device ITO/TPD/ Eu‐85 /Alq 3 /Al reached a maximum luminance of 180 cd m −2 . After that, Liang and Zhang et al introduced oxadiazole and carbazole group into Eu‐83 and synthesized Eu‐86 and Eu‐87 (Scheme ). The device showed a better but still moderate performance.…”

A tris β-diketonate europium(III) complex based OLED fabricated by thermal evaporation method displaying efficient bright red emission

“…The complex exhibited B = 322 cd/m 2 and current efficiency (ηc) = 1.9 cd/A at 21V. Zhang et al, [8] modified the ancillary ligand with the holetransporting carbazole moiety and synthesized a new [Eu(dbm)3(Car-Py-Im)] (dbm = dibenzoylmethanato and Car-Py-Im = 9-(5-(2-(pyridin-2-yl)-1H-benzo [d]imidazol-1-yl)pentyl)-4a,4b,8a,9a-tetrahydro-9H-carbazole) which, when incorporated into a device, gives a better hole-transport ability compared to the unsubstituted Py-Im complex. The complex displayed B = 200 cd/m 2 at 20 V and ηc = 4.2 cd/A at 0.5 mA/cm 2 .…”

“…The complex displayed B = 200 cd/m 2 at 20 V and ηc = 4.2 cd/A at 0.5 mA/cm 2 . However, the EL performance of devices using the family of Py-Im complexes have very high operating voltages (10 -21 V) which limits their use in real-life applications [6][7][8][9] ) and the energy transfer (ET) process. Finally, we have successfully employed Eu-1 was as an emitter to fabricate single-and double-EML red-emitting EL devices.…”