• Synthesis, photophysical, electrochemical and electroluminescence studies of red emitting phosphorescent Ir(III) heteroleptic complexes

    • Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/jcsc/129/09/1391-1398

    • Keywords

       

      1-Phenyl-isoquinoline; Suzuki-Miyaura coupling; Iridium(III)complex; phosphorescence; red emitter; electroluminescence.

    • Abstract

       

      Five heteroleptic, cyclometalated (CN) Iridium(III) complexes of acetylacetone (acac) and 1-phenyl-isoquinoline (piq) derivatives, Ir(acac)(piq) ₂, Ir(acac)(2,4-difluoro-piq) ₂, Ir(acac)(4-trifluoromethylpiq) ₂, Ir(acac)(4-N,N-dimethyl-piq) ₂, Ir(acac)(4-acetyl-piq) ₂, were synthesized and characterized. The ((CN) ₂ Ir(acac) complexes in toluene showed phosphorescence (λmax = 598 nm to 658 nm) with quantum yields (0.1 to 0.32) and microsecond lifetimes (0.43 to 1.9 μs). The complexes were non-luminescent in thin films due to self-quenching but luminescent when lightly doped (5%) in a host organic material, 4,4' -Bis(Ncarbazolyl)- 1,1' -biphenyl (CBP). The HOMO levels determined using cyclic voltammetric oxidation potentials were in the range−5.48 to−5.80 eV. Electroluminescence properties and performance of the Ir complexes dopedin CBP (active layer) were studied in a multilayer (ITO/F4TCNQ/TPD/doped CBP/BCP/LiF/Al) organic light emitting device (OLED). The electroluminescense (EL) spectra of the device matched with the phosphorescent spectra of the Ir complexes. The turn-on voltage at ∼4.5 V, maximum brightness of 7600 cd/m² and current efficiency of ∼7.0 cd/A at a brightness of ∼100 cd/m² indicate that these are promising OLED materials.

    • Author Affiliations

       

      FARMAN ALI1 2 PABITRA K NAYAK1 3 N PERIASAMY1 4 NEERAJ AGARWAL1 5

      1. Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005, India
      2. Department of Applied Chemistry, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
      3. Clarendon Laboratory, University of Oxford, Oxford OX1 3PU, UK
      4. 303, Golf Manor, Wind Tunnel Road, Bengaluru 560 017, India
      5. UM-DAE, Centre for Excellence in Basic Sciences, Health Centre Building, Kalina Campus, Santacruz (E), Mumbai 400 098, India
    • Dates

       
    • Supplementary Material

       
  • Journal of Chemical Sciences | News

© 2021-2022 Indian Academy of Sciences, Bengaluru.