Xu Bingjia, He Jiajun, Mu Yingxiao, Zhu Qiangzhong, Wu Sikai, Wang Yifan, Zhang Yi, Jin Chongjun, Lo Changcheng, Chi Zhenguo, Lien Alan, Liu Siwei, Xu Jiarui
PCFM Lab , GD HPPC Lab , Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films , State Key Laboratory of Opto-electronic Material and Technologies , School of Chemistry and Chemical Engineering , Sun Yet-sen University , Guangzhou 510275 , China . Email:
State Key Laboratory of Optoelectronic Material and Technologies , School of Physics and Engineering , Sun Yat-sen University , Guangzhou 510275 , China.
Chem Sci. 2015 May 1;6(5):3236-3241. doi: 10.1039/c5sc00466g. Epub 2015 Mar 18.
Organic materials exhibiting mechanoluminescence (ML) are promising for usage in displays, lighting and sensing. However, the mechanism for ML generation remains unclear, and the light-emitting performance of organic ML materials in the solid state has been severely limited by an aggregation-caused quenching (ACQ) effect. Herein, we present two strongly photoluminescent polymorphs (, C and C) with distinctly different ML activities based on a tetraphenylethene derivative PTA. As an aggregation-induced emission (AIE) emitter, PTA perfectly surmounted the ACQ, making the resultant block-like crystals in the C phase exhibit brilliant green ML under daylight at room temperature. The ML-inactive prism-like crystals C can also have their ML turned on by transitioning toward C with the aid of dichloromethane vapor. Moreover, the C polymorph shows ML and mechanochromism simultaneously and respectively without and with UV irradiation under a force stimulus, thus suggesting a feasible design direction for the development of efficient and multifunctional ML materials.
具有机械发光（ML）特性的有机材料在显示器、照明和传感领域具有广阔的应用前景。然而，ML产生的机制尚不清楚，并且固态有机ML材料的发光性能受到聚集诱导猝灭（ACQ）效应的严重限制。在此，我们基于四苯乙烯衍生物PTA展示了两种具有明显不同ML活性的强发光多晶型物（C和C）。作为聚集诱导发光（AIE）发光体，PTA完美地克服了ACQ效应，使得在室温日光下，C相中的块状晶体呈现出明亮的绿色ML。ML不活跃的棱柱状晶体C在二氯甲烷蒸气的辅助下向C转变时，其ML也可以被开启。此外，C多晶型物在力刺激下分别在无紫外光照射和有紫外光照射时同时且分别表现出ML和机械变色，因此为高效多功能ML材料的开发提出了一个可行的设计方向。
