Molecular Design of Thermally Activated Delayed-Fluorescent Emitters Using 2,2'-Bipyrimidine as the Acceptor in Donor-Acceptor Structures

Hee-Jun Park; Si Hyun Han; Jun Yeob Lee

doi:10.1002/asia.201700889

Molecular Design of Thermally Activated Delayed-Fluorescent Emitters Using 2,2'-Bipyrimidine as the Acceptor in Donor-Acceptor Structures

Chem Asian J. 2017 Sep 19;12(18):2494-2500. doi: 10.1002/asia.201700889. Epub 2017 Aug 15.

Authors

Hee-Jun Park¹, Si Hyun Han¹, Jun Yeob Lee¹

Affiliation

¹ School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 440-746, Korea.

PMID: 28695621
DOI: 10.1002/asia.201700889

Abstract

Donor-acceptor-donor (D-A-D)-type thermally activated delayed fluorescence (TADF) emitters 5,5'-bis{4-[9,9-dimethylacridin-10(9H)-yl]phenyl}-2,2'-bipyrimidine (Ac-bpm) and 5,5'-bis[4-(10H-phenoxazin-10-yl)phenyl]-2,2'-bipyrimidine (Px-bpm), based on the 2,2'-bipyrimidine accepting unit, were developed and their TADF devices were fabricated. The orthogonal geometry between the donor unit and the 2,2'-bipyrimidine accepting core facilitated a HOMO/LUMO spatial separation, thus realizing thermally activated delayed fluorescence. The exhibited electroluminescence ranged from green to yellow, depending on the donor unit, with maximum external quantum efficiencies of up to 17.1 %.

Keywords: donor-acceptor systems; fluorescence; heterocycles; luminescence; molecular devices.