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Highly effective organic light-emitting diodes containing thermally activated delayed fluorescence emitters with horizontal molecular orientation.

ABSTRACT: In this study, we report new thermally activated delayed fluorescence (TADF) emitters, AcPYM (10,10'-(pyrimidine-2,5-diylbis(4,1-phenylene))bis(9,9-dimethyl-9,10-dihydroacridine)) and PxPYM (10,10'-(pyrimidine-2,5-diylbis(4,1-phenylene))bis(10H-phenoxazine)), by employing donor units at the 2,5-positions of the pyrimidine acceptor unit. The donor-acceptor-donor (D-A-D) units combined in the linear molecular structure of AcPYM or PxPYM enhanced the horizontally oriented alignment, and the horizontal transition dipole moments were realized by up to 87% in the host matrix. Organic light-emitting diodes (OLEDs) containing AcPYM and PxPYM emitters realized external quantum efficiencies (η _ext) of 16.8% for blue and green emissions.

SUBMITTER: Lee CH

PROVIDER: S-EPMC9058249 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Highly effective organic light-emitting diodes containing thermally activated delayed fluorescence emitters with horizontal molecular orientation.

Lee Chan Hee CH Choi Shin Hyung SH Oh Sung Joon SJ Lee Jun Hyeon JH Shim Jae Won JW Adachi Chihaya C Lee Sae Youn SY

RSC advances 20201126 70

In this study, we report new thermally activated delayed fluorescence (TADF) emitters, AcPYM (10,10'-(pyrimidine-2,5-diylbis(4,1-phenylene))bis(9,9-dimethyl-9,10-dihydroacridine)) and PxPYM (10,10'-(pyrimidine-2,5-diylbis(4,1-phenylene))bis(10<i>H</i>-phenoxazine)), by employing donor units at the 2,5-positions of the pyrimidine acceptor unit. The donor-acceptor-donor (D-A-D) units combined in the linear molecular structure of AcPYM or PxPYM enhanced the horizontally oriented alignment, and the ...[more]

PMID: 35514925

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