Scientific Reports (Jul 2017)

An optical and electrical study of full thermally activated delayed fluorescent white organic light-emitting diodes

  • Daniel de Sa Pereira,
  • Paloma L. dos Santos,
  • Jonathan S. Ward,
  • Przemyslaw Data,
  • Masato Okazaki,
  • Youhei Takeda,
  • Satoshi Minakata,
  • Martin R. Bryce,
  • Andrew P. Monkman

DOI
https://doi.org/10.1038/s41598-017-06568-3
Journal volume & issue
Vol. 7, no. 1
pp. 1 – 8

Abstract

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Abstract We report on the engineering of full thermally activated delayed fluorescence – based white organic light emitting diodes (W-OLEDs) composed of three emitters (2,7-bis(9,9-dimethyl-acridin-10-yl)-9,9-dimethylthioxanthene-S,S-dioxide (DDMA-TXO2), 2,7-bis(phenoxazin-10-yl)-9,9-dimethylthioxanthene-S,S-dioxide (DPO-TXO2) and 3,11-di(10H-phenoxazin-10-yl)dibenzo[a,j]phenazine (POZ-DBPHZ) in two different hosts. By controlling the device design through the study of the emission of DDMA-TXO2 and DPO-TXO2, the behaviour of POZ-DBPHZ in a device with more than one emitter, and the combination of the three materials, respectively, we show that external quantum efficiencies as high as 16% can be obtained for a structure with a correlated colour temperature close to warm white, together with colour rendering index close to 80. However it is in their performance stability that provides the true breakthrough: at 1000 cd/m2 the efficiencies were still above 10%, which is one of the best for this type of devices.