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Realization of high-efficiency fluorescent organic light-emitting diodes with low driving voltage.

ABSTRACT: It is commonly accepted that a full bandgap voltage is required to achieving efficient electroluminescence (EL) in organic light-emitting diodes. In this work, we demonstrated organic molecules with a large singlet-triplet splitting can achieve efficient EL at voltages below the bandgap voltage. The EL originates from delayed fluorescence due to triplet fusion. Finally, in spite of a lower quantum efficiency, a blue fluorescent organic light-emitting diode having a power efficiency higher than some of the best thermally activated delayed fluorescent and phosphorescent blue organic light-emitting diodes is demonstrated. The current findings suggest that leveraging triplet fusion from purely organic molecules in organic light-emitting diode materials offers an alternative route to achieve stable and high efficiency blue organic light-emitting diodes.

SUBMITTER: Salehi A

PROVIDER: S-EPMC6534605 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Realization of high-efficiency fluorescent organic light-emitting diodes with low driving voltage.

Salehi Amin A Dong Chen C Shin Dong-Hun DH Zhu Liping L Papa Christopher C Thy Bui Anh A Castellano Felix N FN So Franky F

Nature communications 20190524 1

It is commonly accepted that a full bandgap voltage is required to achieving efficient electroluminescence (EL) in organic light-emitting diodes. In this work, we demonstrated organic molecules with a large singlet-triplet splitting can achieve efficient EL at voltages below the bandgap voltage. The EL originates from delayed fluorescence due to triplet fusion. Finally, in spite of a lower quantum efficiency, a blue fluorescent organic light-emitting diode having a power efficiency higher than s ...[more]

PMID: 31127103

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