Zhao Xiaoyu, Sukhanov Andrey A, Jiang Xiao, Zhao Jianzhang, Voronkova Violeta K
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, P. R. China.
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830017, P. R. China.
J Phys Chem Lett. 2022 Mar 24;13(11):2533-2539. doi: 10.1021/acs.jpclett.2c00435. Epub 2022 Mar 14.
A long-lived triplet charge separated state (CS state lifetime: 0.56 μs) was observed in a electron donor-acceptor dyad with electron donor phenothiazine (PTZ) and acceptor anthraquinone (AQ) directly connected by a single C-N bond (). The CS state energy (2.0 eV in cyclohexane) is lower than those of the AQ (2.7 eV) or the PTZ state (2.6 eV). By oxidation of the PTZ unit, thus increasing of the CS state energy (2.7 eV in cyclohexane), thermally activated delayed fluorescence (TADF) was observed [τ = 17.7 ns (99.9%)/1.5 μs (0.1%)]. Time-resolved electron paramagnetic resonance (TREPR) spectra confirm the electron spin multiplicity of the CS state, and the zero-field-splitting (ZFS) parameters || and || are 48.2 mT and 11.2 mT, respectively. These results are useful for design of compact electron donor-acceptor dyads to access the long-lived CS state and study the TADF mechanism.
在一种电子供体 - 受体二元体系中观察到了长寿命的三重态电荷分离态（CS态寿命：0.56 μs），该二元体系中电子供体吩噻嗪（PTZ）和受体蒽醌（AQ）通过单个C - N键直接相连（）。CS态能量（在环己烷中为2.0 eV）低于AQ态（2.7 eV）或PTZ态（2.6 eV）。通过氧化PTZ单元，从而提高CS态能量（在环己烷中为2.7 eV），观察到了热激活延迟荧光（TADF）[τ = 17.7 ns（99.9%）/1.5 μs（0.1%）]。时间分辨电子顺磁共振（TREPR）光谱证实了CS态的电子自旋多重性，零场分裂（ZFS）参数||和||分别为48.2 mT和11.2 mT。这些结果对于设计紧凑的电子供体 - 受体二元体系以获得长寿命的CS态并研究TADF机制很有用。
