Chen Fan, Hu Jun, Wang Xingdong, Shao Shiyang, Wang Lixiang, Jing Xiabin, Wang Fosong
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, China.
Front Chem. 2019 Dec 10;7:854. doi: 10.3389/fchem.2019.00854. eCollection 2019.
We report the design, synthesis and electroluminescent properties of three kinds of through-space charge transfer (TSCT) polymers consisting of non-conjugated polystyrene backbone, acridan donor and triarylboron acceptors having different substituents such as hydrogen (H), fluorine (F), and trifluoromethyl (CF). Owing to the weak electron interaction between acridan donor and triarylboron acceptor through non-conjugated connection, blue emission with peaks in range of 429-483 nm can be achieved for the polymers in solid-state film, accompanied with photoluminescence quantum yields of 26-53%. The resulting TSCT polymers exhibit small ΔE values below 0.1 eV owing to the separated HOMO and LUMO distributions, showing thermally activated delayed fluorescence with lifetimes in range of 0.19-0.98 μs. Meanwhile, the polymers show aggregation-induced emission (AIE) effect with the emission intensity increased by up to ~33 folds from solution to aggregation state. Solution-processed organic light-emitting diodes based on the polymers containing trifluoromethyl substituent exhibit promising electroluminescent performance with maximum luminous efficiency of 20.1 cd A and maximum external quantum efficiency of 7.0%, indicating that they are good candidates for development of luminescent polymers.
我们报道了三种通过空间电荷转移（TSCT）聚合物的设计、合成及电致发光性质，这些聚合物由非共轭聚苯乙烯主链、吖啶供体和具有不同取代基（如氢（H）、氟（F）和三氟甲基（CF））的三芳基硼受体组成。由于吖啶供体和三芳基硼受体之间通过非共轭连接的电子相互作用较弱，这些聚合物在固态薄膜中可实现峰值在429 - 483 nm范围内的蓝光发射，同时光致发光量子产率为26 - 53%。由于最高占据分子轨道（HOMO）和最低未占据分子轨道（LUMO）分布分离，所得的TSCT聚合物表现出低于0.1 eV的小ΔE值，显示出热激活延迟荧光，寿命在0.19 - 0.98 μs范围内。同时，这些聚合物表现出聚集诱导发光（AIE）效应，从溶液态到聚集态发射强度增加高达约33倍。基于含三氟甲基取代基聚合物的溶液处理有机发光二极管表现出有前景的电致发光性能，最大发光效率为20.1 cd/A，最大外量子效率为7.0%，表明它们是发光聚合物开发的良好候选材料。
