Bright and efficient red emitting electroluminescent devices fabricated from ternary europium complexes

Muhammad S. Khan, Rashid Ilmi, Weidong Sun, José D.L. Dutra, Willyan F. Oliveira, Liang Zhou, Wai Yeung Wong (Corresponding Author), Paul R. Raithby

Research output: Journal article publicationJournal articleAcademic researchpeer-review

26 Citations (Scopus)


The photophysical properties of two previously synthesized, highly efficient, bright red emitting complexes [Eu(btfa)3DPEPO] (CIE, 0.672; 0.326) (Eu-1) and [Eu(nta)3DPEPO] (CIE, 0.673; 0.326) (Eu-2) (btfa = 4,4,4-trifluoro-1-phenyl-1,3-butanedione, nta = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione and DPEPO = bis(2-(diphenylphosphino)phenyl)ether oxide) are reported. The complexes have been used as dopants to fabricate several single and double emitting layer (EML) electroluminescent (EL) devices. At the optimum doping concentration of 4 wt%, the single EML device ofEu-1exhibited a pure red color with an external quantum efficiency (EQE) of 2.9% and a maximum brightness (B) = 1320 cd m−2, maximum current efficiency (ηc) = 4.08 cd A−1, maximum power efficiency (ηp) = 3.37 lm W−1with a very low turn-on voltage (Vturn-on) = 3.8 V. Importantly, the single EML device ofEu-2at the optimum doping concentration exhibited pure red EL with EQE of 6.0% with the best EL performance:B= 2108 cd m−2c= 8.45 cd A−1, andηp= 6.98 lm W−1at a very lowVturn-on= 3.5 V. The performances of this device are among the best reported for devices incorporating a europium complex as a red emitter. Furthermore, the EL performances were achieved at the current density of 10 mA cm−2, thereby alleviating a serious efficiency roll-off as a major obstacle to the development of Eu-complex based EL devices.

Original languageEnglish
Pages (from-to)5600-5612
Number of pages13
JournalJournal of Materials Chemistry C
Issue number16
Publication statusPublished - 28 Apr 2020

ASJC Scopus subject areas

  • General Chemistry
  • Materials Chemistry


Dive into the research topics of 'Bright and efficient red emitting electroluminescent devices fabricated from ternary europium complexes'. Together they form a unique fingerprint.

Cite this