| 초록 |
Two D-A-D type thermally activated delayed fluorescence (TADF) materials (Ac-bpm, Px-bpm) using acridine (Ac) or phenoxazine (Px) as an electron donor and 2,2'-bipyrimidine (bpm) as an electron acceptor were developed and used as the emissive dopants. The EL devices fabricated using Ac-bpm and Px-bpm displayed a green emission (CIEx, CIEy = 0.29, 0.53) with an EQE of 17.1% and a yellow emission (CIEx, CIEy = 0.41, 0.54) with an EQE of 14.4%, respectively. A device using Px-bpm showed a reduced efficiency roll-off compared to that of Ac-bpm, presumably due to a shorter excited state lifetime for the TADF emission. |
