Triplet photodynamic and up-conversion luminescence in donor–acceptor dyads with slip-stacked vs. co-facial arrangement
Triplet photodynamic and up-conversion luminescence in donor–acceptor dyads with slip-stacked vs. co-facial arrangement
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滑堆积与共面排列的供体-受体二元体中的三重态光动力和上转换发光
DOI：
10.1039/d1tc05122a
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发表时间：
2022
影响因子：
6.4
通讯作者：
Ayitou, A. Jean-Luc
中科院分区：
文献类型：
--
作者：
Yun, Young Ju;Peccati, Francesca;Wiederrecht, Gary P.;Gosztola, David J.;Diroll, Benjamin T.;Jiménez-Osés, Gonzalo;Ayitou, A. Jean-Luc
有机给体-受体(D-A)二联体的设计、合成和表征可以提供宝贵的数据，从而提高经典的光诱导双分子相互作用/过程的效率。本文合成了两个新的三联体D-A二联体(4和5)，并对其进行了全表征。虽然这些新体系的吸收和发射光谱与三重态给电子体/敏化剂奎诺硫酰胺(QDN)相似，但这两个二元体的瞬时吸收(TA)谱产生了与三重态瞬变和电荷转移物种相关的新特征。然而，激发态过程/动力学的动力学受给体/受体生色团的几何排列(S)的显著影响。对TA数据的进一步分析表明，具有滑移堆栈几何结构的二分体(4)在进行二分体内部和二分体之间的三线态能量转移方面不如具有共面几何结构的二分体(5)有效。随后，9，10-二苯基菲(DPA)的三重态敏化通过三重态-三重态湮灭DPA三重态的瞬变导致了上转换发光。但是，研究发现，使用共面型二元体5可以在较低的功率密度下获得最大的上转换量子产率。这些结果为设计可用于光捕获/调制应用的三重态施主-受体二元体提供了有价值的指导。
The design/synthesis and characterization of organic donor–acceptor (D–A) dyads can provide precious data allowing to improve the efficiency of classical photo-induced bimolecular interactions/processes. In this report, two novel triplet D–A dyads (4 and 5) were synthesized and fully characterized. While the optical absorption and emission profiles of these new systems exhibit similar spectral structures as that of the triplet donor/sensitizer quinoidal thioamide (QDN), the transient absorption (TA) spectra of these two dyads produced new features that can be associated with triplet transients and charge transfer species. However, the kinetics of the excited-state processes/dynamics is significantly influenced by the geometrical arrangement(s) of donor/acceptor chromophores. Further analysis of the TA data suggests that the dyad with slip-stack geometry (4) is less effective in undergoing both intra- and inter-dyad triplet energy transfer than the dyad with co-facial geometry (5). Subsequently, triplet sensitization of 9,10-diphenylanthracene (DPA) using both dyads led to upconverted photoluminescence via triplet–triplet annihilation of DPA triplet transients. But, it was found that a maximum upconversion quantum yield could be achieved at a low power density using the co-facial type dyad 5. Altogether, these results provide valuable guidance in the design of triplet donor–acceptor dyads, which could be used for light-harvesting/modulation applications.