Efficient Red Organic Light Emitting Diodes of Nona Coordinate Europium Tris(β-diketonato) Complexes Bearing 4'-Phenyl-2,2':6',2''- terpyridine

Rashid Ilmi, Jingyu Wang, José D.L. Dutra, Liang Zhou, Wei-Yeung Wong, Paul R. Raithby, Muhammad Khan

Research output: Contribution to journalArticlepeer-review

11 Citations (SciVal)
2 Downloads (Pure)

Abstract

Two novel nona-coordinated Eu(III) complexes [Eu(btfa) 3(Ph-TerPyr)] (Eu-1) and [Eu(NTA) 3(Ph-TerPyr)] (Eu-2) have been synthesized and characterized. The structure of the complexes was elucidated by density functional theory (DFT) methods. The experimental photophysical properties of the complexes were investigated and complemented with theoretical calculations. Effective energy transfer (ET) pathways for the sensitized red luminescence is discussed. The complexes were tested as emitting layers (EML) in organic light emitting diodes (OLEDs). At the optimum doping concentration of 4 wt.%, the double-EML OLEDs of Eu-1 exhibited red electroluminescence (EL) with an EQE of 4.0 % and maximum brightness (B)=1179 cd/m 2, maximum current efficiency (η c)=5.64 cd/A, and maximum power efficiency (η p)=4.78 lm/W at the current density (J) of 10 mA/cm 2. Interestingly, the double-EML OLEDs of Eu-2 at the optimum concentration of 3 wt.%, displayed an outstanding EL performance with EQE of 7.32 % and B=838 cd/m 2, η c=10.19 cd/A and η p=10.33 lm/W at J=10 mA/cm 2. The EL performance of this device is among the best reported for devices incorporating a europium complex as a red emitter.

Original languageEnglish
Article numbere202300376
Number of pages13
JournalChemistry - A European Journal
Volume29
Issue number37
Early online date16 Apr 2023
DOIs
Publication statusPublished - 3 Jul 2023

Bibliographical note

Funding Information:
MSK acknowledges His Majesty's Trust Fund for Strategic Research (Grant No. SR/SQU/SCI/CHEM/21/01) and The Ministry of Higher Education, Research and Innovation (MoHERI), Oman (Grant: RC/RG‐SCI/CHEM/22/01) for funding. RI thanks HM′s Trust Fund for a postdoctoral fellowship. JDLD appreciates the financial support from the Brazilian funding agencies CAPES, CNPq (421733/2018‐7), FACEPE (APQ‐0675‐1.06/14) and FAPITEC‐SE (FAPITEC/SE/FUNTEC N° 06/2021), and thanks Gabriel Silva Santos for calculating the ligand decay rates and the emission quantum yield of the compounds. LZ is grateful for the financial aid from the National Natural Science Foundation of China (62174160). WYW thanks the Hong Kong Research Grants Council (PolyU 15305320), Guangdong‐Hong Kong‐Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials (2019B121205002), the CAS‐Croucher Funding Scheme for Joint Laboratories (ZH4A), Hong Kong Polytechnic University, Research Institute for Smart Energy (CDAQ) and the Endowed Professorship in Energy from Miss Clarea Au (847S) for the financial support. PRR is grateful to the Engineering and Physical Sciences Research Council (EPSRC) for funding (Grant EP/K004956/1).

Funding Information:
MSK acknowledges His Majesty's Trust Fund for Strategic Research (Grant No. SR/SQU/SCI/CHEM/21/01) and The Ministry of Higher Education, Research and Innovation (MoHERI), Oman (Grant: RC/RG-SCI/CHEM/22/01) for funding. RI thanks HM′s Trust Fund for a postdoctoral fellowship. JDLD appreciates the financial support from the Brazilian funding agencies CAPES, CNPq (421733/2018-7), FACEPE (APQ-0675-1.06/14) and FAPITEC-SE (FAPITEC/SE/FUNTEC N° 06/2021), and thanks Gabriel Silva Santos for calculating the ligand decay rates and the emission quantum yield of the compounds. LZ is grateful for the financial aid from the National Natural Science Foundation of China (62174160). WYW thanks the Hong Kong Research Grants Council (PolyU 15305320), Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials (2019B121205002), the CAS-Croucher Funding Scheme for Joint Laboratories (ZH4A), Hong Kong Polytechnic University, Research Institute for Smart Energy (CDAQ) and the Endowed Professorship in Energy from Miss Clarea Au (847S) for the financial support. PRR is grateful to the Engineering and Physical Sciences Research Council (EPSRC) for funding (Grant EP/K004956/1).

Publisher Copyright:
© 2023 Wiley-VCH GmbH.

Keywords

  • DFT calculations
  • Electroluminescence
  • Europium(III)
  • Sensitized Luminescence
  • β-diketone

ASJC Scopus subject areas

  • Chemistry(all)
  • Catalysis
  • Organic Chemistry

Fingerprint

Dive into the research topics of 'Efficient Red Organic Light Emitting Diodes of Nona Coordinate Europium Tris(β-diketonato) Complexes Bearing 4'-Phenyl-2,2':6',2''- terpyridine'. Together they form a unique fingerprint.

Cite this