Polymer Bulletin

, Volume 76, Issue 12, pp 6429–6436 | Cite as

The contribution of triplet excitons to the total singlet production yield in a sky-blue emitting co-polymer film

  • Murat AydemirEmail author
Original Paper


In this work, the complex excited state dynamics of a sky-blue emitting co-polymer {poly-[9,9′-dioctylfluorene-co-bis-N,N′-(4-butylphenyl)-bis-N,N′-phenyl-1,4-phenylenediamine]} is determined, using a time-resolved gated spectroscopy method, which helps to investigate the origin of delayed fluorescence in thin film. It is clearly shown that delayed fluorescence arises from triplet–triplet annihilation mechanism, which opens an indirect pathway to generate singlet excitons. Experimentally, the delayed fluorescence yield varies from 20% at room temperature to 46 ± 2% at 20 K, suggesting that an alternative triplet harvesting mechanism is operative to convert the triplet into emissive singlet states.


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

289_2019_2729_MOESM1_ESM.docx (32 kb)
Supplementary material 1 (DOCX 32 kb)


  1. 1.
    Burroughes JH, Bradley DDC, Brown AR et al (1990) Light-emitting diodes based on conjugated polymers. Nature 347:539–541CrossRefGoogle Scholar
  2. 2.
    Liang J, Li L, Niu X, Yu Z, Pei Q (2013) Elastomeric polymer light-emitting devices and displays. Nat Photon 7:817–824CrossRefGoogle Scholar
  3. 3.
    Kondakov DY (2009) Role of triplet–triplet annihilation in highly efficient fluorescent devices. J Soc Inf Disp 17:137–144CrossRefGoogle Scholar
  4. 4.
    Aydemir M, Vygintas J, Fernando BD, Andrew PM (2015) Inter/intrachain interactions behind the formation of charge transfer states in polyspirobifluorene: a case study for complex excited-state dynamics in different polarity index solvents. J Phys Chem C 119:5855–5863CrossRefGoogle Scholar
  5. 5.
    Aydemir M, Haykır G, Battal A, Jankus V et al (2016) High efficiency OLEDs based on anthracene derivatives: the impact of electron donating and withdrawing group on the performance of OLED. Org Electron 30:149–157CrossRefGoogle Scholar
  6. 6.
    Jankus V, Aydemir M, Dias FB, Monkman AP (2016) Generating light from upper excited triplet states: a contribution to the indirect singlet yield of a polymer OLED, helping to exceed the 25% singlet exciton limit. Adv Sci 3:1500221CrossRefGoogle Scholar
  7. 7.
    Kondakov DY, Pawlik TD, Hatwar TK, Spindler JP (2009) Triplet annihilation exceeding spin statistical limit in highly efficient fluorescent organic light-emitting diodes. J Appl Phys 106:124510CrossRefGoogle Scholar
  8. 8.
    Kondakov DY (2015) Triplet–triplet annihilation in highly efficient fluorescent organic light-emitting diodes: current state and future outlook. Philos Trans R Soc Math Phys Eng Sci 373:20140321CrossRefGoogle Scholar
  9. 9.
    Köhler A, Bässler H (2015) Electronic processes in organic semiconductors: an introduction. Wiley, New YorkCrossRefGoogle Scholar
  10. 10.
    Palilis L, Lidzey D, Redecker M et al (2001) High performance blue light-emitting diodes based on conjugated polymer blends. Synth Met Synth Met 121:1729–1730CrossRefGoogle Scholar
  11. 11.
    Snaith HJ, Arias AC, Morteani AC, Silva C, Friend RH (2002) Charge generation kinetics and transport mechanisms in blended polyfluorene photovoltaic devices. Nano Lett Nano Lett 2:1353–1357CrossRefGoogle Scholar
  12. 12.
    Arias AC, MacKenzie JD, Stevenson R et al (2001) Photovoltaic performance and morphology of polyfluorene blends: a combined microscopic and photovoltaic investigation. Macromolecules 34:6005–6013CrossRefGoogle Scholar
  13. 13.
    Müllen K, Scherf U (2006) Organic light-emitting devices: synthesis, properties, and applications. Wiley, New YorkGoogle Scholar
  14. 14.
    Clare T (1986) An investigation of plasma polymerization and copolymerization using fluoroaromatic compounds, Dissertation, Durham UniversityGoogle Scholar
  15. 15.
    Morteani AC, Friend RH, Silva C (2004) Endothermic exciplex–exciton energy-transfer in a blue-emitting polymeric heterojunction system. Chem Phys Lett 391:81–84CrossRefGoogle Scholar
  16. 16.
    Morteani AC, Dooht AS, Kim JS, Silva C et al (2003) Barrier-free electron–hole capture in polymer blend heterojunction light-emitting diodes. Adv Mater 15:1708CrossRefGoogle Scholar
  17. 17.
    Rothe C, Monkman AP (2003) Triplet exciton migration in a conjugated polyfluorene. Phys Rev B 68:075208CrossRefGoogle Scholar
  18. 18.
    Cheung ECC (2010) Evolution of optical gain properties through three generations of electroluminescent fluorene-based polymers, Dissertation, Imperial College LondonGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Fundamental Sciences, Faculty of ScienceErzurum Technical UniversityErzurumTurkey

Personalised recommendations