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Thermally Activated Delayed Fluorescence Host for High Performance Organic Light-Emitting Diodes.

ABSTRACT: Thermally activated delayed florescence (TADF) materials can be an efficient host in organic LED (OLED). It is because it is possible to couple energetically the emission energy level of a dopant to the energy levels in the TADF material. In this work fluorescent emitters 2,3,6,7-tetrahydro-1,1,7,7,-tetramethyl-1H,5 H,11H-10-(2-benzothiazolyl)quinolizino-9,9a,1gh coumarin (c545t) and 5,6,11,12-tetraphenyltetracene (rubrene) were used as dopants in a blended TADF host; tris(4-carbazoyl-9-ylphenyl)amine (TCTA) with 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine (Tm3PyBPZ). The blended TADF host has an energy difference between the singlet and triplet excited states (ΔE_ST) around 27 meV with the yield of reverse intersystem crossing (Ф_RISC) nearly 100%. This high Ф_RISC yield enhances the OLED performance with the c545t doped OLED having 11.9% external quantum efficiency and 10% for the rubrene doped OLED.

SUBMITTER: Zhang L

PROVIDER: S-EPMC5995865 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Thermally Activated Delayed Fluorescence Host for High Performance Organic Light-Emitting Diodes.

Zhang Lu L Cheah Kok Wai KW

Scientific reports 20180611 1

Thermally activated delayed florescence (TADF) materials can be an efficient host in organic LED (OLED). It is because it is possible to couple energetically the emission energy level of a dopant to the energy levels in the TADF material. In this work fluorescent emitters 2,3,6,7-tetrahydro-1,1,7,7,-tetramethyl-1H,5 H,11H-10-(2-benzothiazolyl)quinolizino-9,9a,1gh coumarin (c545t) and 5,6,11,12-tetraphenyltetracene (rubrene) were used as dopants in a blended TADF host; tris(4-carbazoyl-9-ylphenyl ...[more]

PMID: 29891928

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