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Design of Efficient Exciplex Emitters by Decreasing the Energy Gap Between the Local Excited Triplet (³LE) State of the Acceptor and the Charge Transfer (CT) States of the Exciplex.

ABSTRACT: A series of thermally activated delayed fluorescence (TADF) exciplex based on the TX-TerPy were constructed. The electronic coupling between the triplet local excited states (³LE) of the donors and acceptor and the charge transfer states had a great influence on the triplet exciton harvesting and ?_PL. Herein, based on this strategy, three donor molecules TAPC, TCTA, and m-MTDATA were selected. The local triplet excited state (³LE) of the three donors are 2.93, 2.72 and 2.52 eV in pure films. And the ³LE of TX-TerPy is 2.69 eV in polystyrene film. The energy gap between the singlet charge transfer (¹CT) states of TAPC:TX-TerPy (7:1), TCTA:TX-TerPy (7:1) and the ³LE of TX-TerPy are 0.30 eV and 0.20 eV. Finally, the ?_PL of TAPC:TX-TerPy (7:1) and TCTA:TX-TerPy (7:1) are 65.2 and 69.6%. When we changed the doping concentration of the exciplex from 15% to 50%, the ratio of the triplet decreased, and ?_PL decreased by half, perhaps due to the increased energy gap between ¹CT and ³LE. Therefore, optimizing the ¹CT, ³CT, and ³LE facilitated the efficient exciplex TADF molecules.

SUBMITTER: Wei X

PROVIDER: S-EPMC6465540 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Design of Efficient Exciplex Emitters by Decreasing the Energy Gap Between the Local Excited Triplet (3LE) State of the Acceptor and the Charge Transfer (CT) States of the Exciplex.

Wei Xiaofang X Liu Yanwei Y Hu Taiping T Li Zhiyi Z Liu Jianjun J Wang Ruifang R Gao Honglei H Hu Xiaoxiao X Liu Guanhao G Wang Pengfei P Lee Chun-Sing CS Wang Ying Y

Frontiers in chemistry 20190409

A series of thermally activated delayed fluorescence (TADF) exciplex based on the TX-TerPy were constructed. The electronic coupling between the triplet local excited states (3LE) of the donors and acceptor and the charge transfer states had a great influence on the triplet exciton harvesting and ΦPL. Herein, based on this strategy, three donor molecules TAPC, TCTA, and m-MTDATA were selected. The local triplet excited state (3LE) of the three donors are 2.93, 2. ...[more]

PMID: 31024884

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Dataset Information

Design of Efficient Exciplex Emitters by Decreasing the Energy Gap Between the Local Excited Triplet (³LE) State of the Acceptor and the Charge Transfer (CT) States of the Exciplex.

Publications

Design of Efficient Exciplex Emitters by Decreasing the Energy Gap Between the Local Excited Triplet (<sup>3</sup>LE) State of the Acceptor and the Charge Transfer (CT) States of the Exciplex.

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