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Highly efficient multi-resonance thermally activated delayed fluorescence material toward a BT.2020 deep-blue emitter.

ABSTRACT: An ultrapure deep-blue multi-resonance-induced thermally activated delayed fluorescence material (DOB2-DABNA-A) is designed and synthesized. Benefiting from a fully resonating extended helical π-conjugated system, this compound has a small ΔE_ST value of 3.6 meV and sufficient spin-orbit coupling to exhibit a high-rate constant for reverse intersystem crossing (k_RISC = 1.1 × 10⁶s^-1). Furthermore, an organic light-emitting diode employing DOB2-DABNA-A as an emitter is fabricated; it exhibits ultrapure deep-blue emission at 452 nm with a small full width at half maximum of 24 nm, corresponding to Commission Internationale de l'Éclairage (CIE) coordinates of (0.145, 0.049). The high k_RISC value reduces the efficiency roll-off, resulting in a high external quantum efficiency (EQE) of 21.6% at 1000 cd m^-2.

SUBMITTER: Ochi J

PROVIDER: S-EPMC10987657 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature

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Highly efficient multi-resonance thermally activated delayed fluorescence material toward a BT.2020 deep-blue emitter.

Ochi Junki J Yamasaki Yuki Y Tanaka Kojiro K Kondo Yasuhiro Y Isayama Kohei K Oda Susumu S Kondo Masakazu M Hatakeyama Takuji T

Nature communications 20240402 1

An ultrapure deep-blue multi-resonance-induced thermally activated delayed fluorescence material (DOB2-DABNA-A) is designed and synthesized. Benefiting from a fully resonating extended helical π-conjugated system, this compound has a small ΔEST value of 3.6 meV and sufficient spin-orbit coupling to exhibit a high-rate constant for reverse intersystem crossing (kRISC = 1.1 × 106 s-1). Furthermore, an organic light-emitting diode employing DOB2-DABNA-A a ...[more]

PMID: 38565868

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