TY - JOUR
T1 - Dipolar and Quadrupolar Luminophores Based on 1,8-Dimethylcarbazole−Triazine Conjugates for High-Efficiency Blue Thermally Activated Delayed Fluorescence OLEDs
AU - Min, Hyukgi
AU - Park, In Seob
AU - Yasuda, Takuma
N1 - Funding Information:
This study was supported in part by Grant‐in‐Aid for JSPS KAKENHI Grant No. JP18H02048 (T. Y.) and JP19 K15651 (I. S. P.), the Research Foundation for Opto‐Science and Technology (T. Y.), the Japan Research Institute of Industrial Science (T. Y.), the Research Foundation for the Electrotechnology of Chubu (T. Y.), and Hirose International Scholarship Foundation (I. S. P.). H. M. acknowledges financial support from the JASSO Honors Scholarship. The authors are grateful for the support provided by the Cooperative Research Program “Network Joint Research Center for Materials and Devices” and the computer facilities at the Research Institute for Information Technology, Kyushu University.
Publisher Copyright:
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2020/1/1
Y1 - 2020/1/1
N2 - As one of the three primary colors indispensable for full-color displays, the development of blue emitters is of great importance and still a difficult challenge for organic light-emitting diodes (OLEDs). Blue organic emitters exhibiting thermally activated delayed fluorescence (TADF) are anticipated to be promising materials as they have the potential to achieve high electroluminescence (EL) efficiencies and suitable color purity. In this paper, highly efficient blue TADF emitters combining 1,8-dimethylcarbazole as a weak donor (D) unit with a triazine-based acceptor (A) core are reported. Unlike unsubstituted carbazole, 1,8-dimethylcarbazole can effectively induce intermolecular twisting between the D-A linkages, thus enhancing the TADF properties. Moreover, a quadrupolar D-A-D-type blue TADF emitter exhibits superior photo- and electroluminescence (EL) properties compared to a dipolar D-A-type counterpart. TADF-OLEDs based on the D-A-D-type emitter featuring the 1,8-dimethylcarbazole−triazine conjugates display a brilliant blue EL emission and furnish a maximum external EL quantum efficiency as high as 21.2 % with CIE color coordinates of (0.16, 0.27).
AB - As one of the three primary colors indispensable for full-color displays, the development of blue emitters is of great importance and still a difficult challenge for organic light-emitting diodes (OLEDs). Blue organic emitters exhibiting thermally activated delayed fluorescence (TADF) are anticipated to be promising materials as they have the potential to achieve high electroluminescence (EL) efficiencies and suitable color purity. In this paper, highly efficient blue TADF emitters combining 1,8-dimethylcarbazole as a weak donor (D) unit with a triazine-based acceptor (A) core are reported. Unlike unsubstituted carbazole, 1,8-dimethylcarbazole can effectively induce intermolecular twisting between the D-A linkages, thus enhancing the TADF properties. Moreover, a quadrupolar D-A-D-type blue TADF emitter exhibits superior photo- and electroluminescence (EL) properties compared to a dipolar D-A-type counterpart. TADF-OLEDs based on the D-A-D-type emitter featuring the 1,8-dimethylcarbazole−triazine conjugates display a brilliant blue EL emission and furnish a maximum external EL quantum efficiency as high as 21.2 % with CIE color coordinates of (0.16, 0.27).
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U2 - 10.1002/cptc.201900186
DO - 10.1002/cptc.201900186
M3 - Article
AN - SCOPUS:85079688133
SN - 2367-0932
VL - 4
SP - 82
EP - 88
JO - ChemPhotoChem
JF - ChemPhotoChem
IS - 1
ER -