Achieving Highly Efficient Pure Organic Single-Molecule White-Light Emitter: The Coenhanced Fluorescence and Phosphorescence Dual Emission by Tailoring Alkoxy Substituents
Achieving Highly Efficient Pure Organic Single-Molecule White-Light Emitter: The Coenhanced Fluorescence and Phosphorescence Dual Emission by Tailoring Alkoxy Substituents
复制标题
实现高效纯有机单分子白光发射体:通过定制烷氧基取代基实现荧光和磷光双发射
DOI:
10.1002/adom.201901995
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发表时间:
2020-02-05
影响因子:
9
通讯作者:
Yang, Bing
中科院分区:
文献类型:
--
作者:
Wen, Yating;Liu, Haichao;Yang, Bing
Developing the single-molecule white-light emitters (SMWLEs) at room temperature is very challenging for pure organic metal-free system, and it is even more challenging to achieve the high efficiency of pure organic SMWLE. Here, alkoxy substituents are tailored at 2-positioned thioxanthone (TX) to finely tune the molecular packing mode and the intermolecular interaction between TX units, and the photoluminescence (PL) efficiency (phi(PL)) of SMWLE is improved successfully from 1.5% (TX) to 45.0% (TX-OCH(CH3)(2)). This simultaneous enhancement of dual emission between fluorescence and phosphorescence can be ascribed to i) a moderate intersystem crossing (ISC) rate for the equilibrium distribution between singlet and triplet excitons, ii) simultaneously accelerated radiative rates of singlet and triplet excitons due to J-aggregation of TX units, and iii) effective suppression of nonradiation through strong hydrogen bond interactions by alkoxy chains. As a result, this work provides a novel molecular design strategy to harvest high-efficiency pure organic SMWLE using a precise manipulation of pi-pi stacking mode and intermolecular interaction by tailoring alkoxy substituents.