Publication Date
11-2019
Department
Ames Laboratory; Physics and Astronomy; Microelectronics Research Center (MRC)
Campus Units
Physics and Astronomy, Ames Laboratory, Microelectronics Research Center (MRC)
OSTI ID+
1570450; 1569739
Report Number
IS-J 10006; IS-J 10057
DOI
10.1016/j.orgel.2019.06.041
Journal Title
Organic Electronics
Volume Number
74
First Page
13
Last Page
22
Abstract
The host in phosphrescent organic light emitting devices (PhOLEDs), showing the thermally activated delayed fluorescence (TADF) charateristic, can effectively overcome the efficiency roll-off. Herein, six bipolar compounds with donor-π-acceptor (D-π-A) and D-π-A-π-D structures have been synthesized using 1,2,4-triazole derivative (TAZ) as an acceptor and phenothiazine (PTZ), phenoxazine (PXZ), and 9, 9-dimethylacridane (DMAC) as donors. The molecular structures were confirmed by 1H NMR, 13C NMR and X-ray single-crystal diffractions. The large steric hindrance endows these molecules with typical TADF features, including the small singlet-triplet energy splitting (Delta E-ST) of 0.08–0.30 eV and completely spatially separate highest occupied molecular orbitals (HOMO) and the lowest unoccupied molecular orbitals (LUMO) electron densities. The PhOLEDs hosted by these novel TADF materials display excellent performances with low efficiency roll-off.
DOE Contract Number(s)
AC 02-07CH11358; 61705156; 21071108; 60976018; 61605138; 201513002-10
Language
en
Publisher
Iowa State University Digital Repository, Ames IA (United States)