Fluorine substituted triazine acceptor based thermally activated delayed fluorescent emitter as an assistant dopant of fluorescent emitter

A fluorine substituted triazine acceptor was developed for blue thermally activated delayed fluorescent (TADF) emitters. 9,9'-((6-(4-Fluomphenyl)-1,3,5-triazine-2,4-diyebis(2,1-phenylene)This(3,6-di-tert-butyl-9H-carbazole) (FTrzTCz) was synthesized by connecting 4-fluomphenyltriazine with 3,6-di-tert-butylcarbazole at ortho position of a phenyl linker. The FTrzTCz emitter showed high efficiency of 18.5% and improved efficiency rolloff. The FTrzTCz also showed high quantum efficiency of 17.8% as an assistant dopant in the green fluorescent devices. The FTrzTCz worked well as a TADF emitter and an assistant dopant of hyperfluorescent devices by suppressed Dexter energy transfer.