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Control of photoluminescence quantum yield and long-lived triplet emission lifetime in organic alloys.

ABSTRACT: Two-component crystalline organic alloys with a wide range of compositional ratios (from 30% to 90% of one component) are employed to tune excited-state lifetimes and photoluminescence quantum yields (PLQYs). Alloy crystals exhibit homogeneous distribution of parent compounds by X-ray crystallography and differential scanning calorimetry. The alloys display a 1.5- to 5-fold enhancement in thermally activated delayed fluorescence (TADF) lifetime, compared to the parent compounds. PLQYs can also be tuned by changing alloy composition. The reverse intersystem crossing and long-lived lifetime of the parent compounds give rise to long-lived TADF in the alloys. Organic alloys enable tunability of both lifetime and efficiency, providing a new perspective on the development of organic long-lived emissive materials beyond the rules established for host-guest doped systems.

SUBMITTER: Xu Z

PROVIDER: S-EPMC9200050 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Control of photoluminescence quantum yield and long-lived triplet emission lifetime in organic alloys.

Xu Zhen Z Hean Duane D Yuan Jennifer J Wolf Michael O MO

Chemical science 20220530 23

Two-component crystalline organic alloys with a wide range of compositional ratios (from 30% to 90% of one component) are employed to tune excited-state lifetimes and photoluminescence quantum yields (PLQYs). Alloy crystals exhibit homogeneous distribution of parent compounds by X-ray crystallography and differential scanning calorimetry. The alloys display a 1.5- to 5-fold enhancement in thermally activated delayed fluorescence (TADF) lifetime, compared to the parent compounds. PLQYs can also b ...[more]

PMID: 35774161

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