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 (?EST) around 27?meV with the yield of reverse intersystem crossing (?RISC) nearly 100%. This high ?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-other | 2018 Jun

REPOSITORIES: biostudies-other