| 초록 |
In this study, blue host materials of the para-terphenyl having a high triplet were synthesized and evaluated. In the case of para-terphenyl, the triplet energy is generally lower than the ortho- or meta- position due to the conjugation length. However, the introduction of bulky substituents such as carbazole may increase triplet energy due to the increase of the dihedral angle in the molecule. This molecular design can be applied as a blue host. In addition, the C-N bond in the host is caused by the injected electrons can be easily decomposed. However, by limiting the exposure of the C-N bond to the outside, degradation due to electron injection can be minimized. Therefore, the blue dopant tBCz-Trz(2,4,6-tris(2-(3,6-di-tert-butyl-9H-carbazol-9-)yl)phenyl)-1,3,5-triazine) was applied and evaluated, among which omCz-pTP(9,9',9'',9'''-([1,1':4',1''-terphenyl]-2',3,3'',5'-tetrayl)tetrakis(9H-carbazole)) showed a maximum EQE of 24.4% and 6.84 hours at LT50@200nit. |
