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Efficient light-emitting electrochemical cells (LECs) based on ionic iridium(III) complexes with 1,3,4-oxadiazole ligands.

Zhang, J; Zhou, L.; Al-Attar, H.A.; Shao, K.; Wang, L.; Zhu., D.; Su, Z.; Bryce, M.R.; Monkman, A.P.

Authors

J Zhang

L. Zhou

H.A. Al-Attar

K. Shao

L. Wang

D. Zhu.

Z. Su



Abstract

Eight new iridium(III) complexes 1-8, with 1,3,4-oxadiazole (OXD) derivatives as the cyclometalated C^N ligand and/or the ancillary N^N ligands are synthesized and their electrochemical, photophysical, and solid-state light-emitting electrochemical cell (LEC) properties are investigated. Complexes 1, 2, 7 and 8 are additionally characterized by single crystal X-ray diffraction. LECs based on complexes 1-8 are fabricated with a structure indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/cationic iridium complex:ionic liquid/Al. LECs of complexes 1–6 with OXD derivatives as the cyclometalated ligands and as the ancillary ligand show yellow luminescence (λmax = 552–564 nm). LECs of complexes 7 and 8 with cyclometalated C^N phenylpyridine ligands and an ancillary N^N OXD ligand show red emission (λmax 616–624 nm). Using complex 7 external quantum efficiency (EQE) values of >10% are obtained for devices (210 nm emission layer) at 3.5 V. For thinner devices (70 nm) high brightness is achieved: red emission for 7 (8528 cd m−2 at 10 V) and yellow emission for 1 (3125 cd m−2 at 14 V).

Citation

Zhang, J., Zhou, L., Al-Attar, H., Shao, K., Wang, L., Zhu., D., …Monkman, A. (2013). Efficient light-emitting electrochemical cells (LECs) based on ionic iridium(III) complexes with 1,3,4-oxadiazole ligands. Advanced Functional Materials, 23(37), 4667-4677. https://doi.org/10.1002/adfm.201300344

Journal Article Type Article
Publication Date 2013-10
Deposit Date Nov 24, 2014
Journal Advanced Functional Materials
Print ISSN 1616-301X
Publisher Wiley
Peer Reviewed Peer Reviewed
Volume 23
Issue 37
Pages 4667-4677
DOI https://doi.org/10.1002/adfm.201300344
Keywords Iridium, 1,3,4-oxadiazole, Electroluminescence, Electrochemical cells, Red emitters, Light-emitting diodes.