The Electroluminescence Mechanism of Solution-Processed TADF Emitter 4CzIPN Doped OLEDs Investigated by Transient Measurements

Molecules. 2016 Oct 14;21(10):1365. doi: 10.3390/molecules21101365.


High efficiency, solution-processed, organic light emitting devices (OLEDs), using a thermally-activated delayed fluorescent (TADF) emitter, 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), are fabricated, and the transient electroluminescence (EL) decay of the device with a structure of [ITO/PEDOT: PSS/4CzIPN 5 wt % doped 4,40-N,N0-dicarbazolylbiphenyl(CBP)/bis-4,6-(3,5-di-4-pyridylphenyl)-2-methylpyrimidine (B4PyMPM)/lithium fluoride (LiF)/Al], is systematically studied. The results shed light on the dominant operating mechanism in TADF-based OLEDs. Electroluminescence in the host-guest system is mainly produced from the 4CzIPN emitter, rather than the exciplex host materials.

Keywords: TADF-based OLEDS; carrier transport and recombination; energy transfer; transient EL.

MeSH terms

  • Energy Transfer
  • Lighting / instrumentation*
  • Luminescence
  • Luminescent Measurements
  • Nitriles / chemistry*


  • Nitriles
  • 1,3-dicyanobenzene