Kim, Kwang Jong Kim, Gyeong Heon Lampande, Raju Ahn, Dae Hyun Im, Joon Beom Moon, Ji Su Lee, Jae Kyun Lee, Jae Yeol Lee, Ju Young Kwon, Jang Hyuk 2024-01-19T23:31:12Z 2024-01-19T23:31:12Z 2021-09-03 2018-02-14 2050-7526 https://pubs.kist.re.kr/handle/201004/121702 In this communication, we report an excellent new highly conjugated and rigid electron donor (diindolocarbazole) for thermally activated delayed fluorescence (TADF) emitters. The donor-acceptor structure with diindolocarbazole donor induces high oscillator strength as well as high probability for the radiative transition, suitable frontier molecular overlap with proper intramolecular charge transfer and a large dihedral angle with out-of-plane structure between electron donor and acceptor; this results in high photoluminescence quantum yield, small singlet-triplet energy splitting, and extremely short delayed fluorescence exciton lifetime. The fabricated organic light emitting diode with new donor applied green emitter exhibits a remarkably high external quantum efficiency of 31.4% without any out-coupling technique. It also shows extremely low efficiency rolloff characteristics with the highest luminance of 71160 cd m(-2) as well as good operational device stability. English ROYAL SOC CHEMISTRY LIGHT DIODES BLUE DEVICES A new rigid diindolocarbazole donor moiety for high quantum efficiency thermally activated delayed fluorescence emitter Article 10.1039/c7tc04852a 1 JOURNAL OF MATERIALS CHEMISTRY C, v.6, no.6, pp.1343 - 1348 JOURNAL OF MATERIALS CHEMISTRY C 6 6 1343 1348 scie scopus 000424652000008 2-s2.0-85041493497 Materials Science, Multidisciplinary Physics, Applied Materials Science Physics Article LIGHT DIODES BLUE DEVICES fluorescence emitter novel TADF emitters DTRZ-DI and TRZ-DI X-Ray crystal structure