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Improving the Luminescence and Stability of Carbon-Centered Radicals by Kinetic Isotope Effect.

ABSTRACT: The kinetic isotope effect (KIE) is beneficial to improve the performance of luminescent molecules and relevant light-emitting diodes. In this work, the influences of deuteration on the photophysical property and stability of luminescent radicals are investigated for the first time. Four deuterated radicals based on biphenylmethyl, triphenylmethyl, and deuterated carbazole were synthesized and sufficiently characterized. The deuterated radicals exhibited excellent redox stability, as well as improved thermal and photostability. The appropriate deuteration of relevant C-H bonds would effectively suppress the non-radiative process, resulting in the increase in photoluminescence quantum efficiency (PLQE). This research has demonstrated that the introduction of deuterium atoms could be an effective pathway to develop high-performance luminescent radicals.

SUBMITTER: Ma Z

PROVIDER: S-EPMC10301369 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Improving the Luminescence and Stability of Carbon-Centered Radicals by Kinetic Isotope Effect.

Ma Zhichao Z Zhang Lintao L Cui Zhiyuan Z Ai Xin X

Molecules (Basel, Switzerland) 20230616 12

The kinetic isotope effect (KIE) is beneficial to improve the performance of luminescent molecules and relevant light-emitting diodes. In this work, the influences of deuteration on the photophysical property and stability of luminescent radicals are investigated for the first time. Four deuterated radicals based on biphenylmethyl, triphenylmethyl, and deuterated carbazole were synthesized and sufficiently characterized. The deuterated radicals exhibited excellent redox stability, as well as imp ...[more]

PMID: 37375360

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