Liu Bin, Di Qi, Liu Wentao, Wang Chenguang, Wang Yue, Zhang Hongyu
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Qianjin Street , Changchun 130012 , P.R. China.
J Phys Chem Lett. 2019 Apr 4;10(7):1437-1442. doi: 10.1021/acs.jpclett.9b00196. Epub 2019 Mar 13.
Organic crystals are easily cracked into pieces or powders under applied stress because of their intrinsic brittle nature. This undesired mechanical property directly limits their application in flexible optical and optoelectronic devices. Herein, we developed a compact single-benzene molecule dimethyl 2,5-bis((2-hydroxyethyl)amino)terephthalate, which was easily crystallized to form two polymorphs, A and B. Featuring a single-benzene π-system, both polymorphs A and B display red fluorescence in crystals. More importantly, crystals of polymorph A are flexible and can be elastically bent under mechanical force. Given these advantages, a flexible optical waveguide has been realized in the crystal of polymorph A with a bent shape, highlighting its potential application in flexible devices. In addition, the thermal transformation of crystals from polymorph A to polymorph B, which was accompanied by the change of optical property as well as mechanical elasticity, has been observed.
有机晶体由于其固有的脆性，在施加应力时很容易裂成碎片或粉末。这种不理想的机械性能直接限制了它们在柔性光学和光电器件中的应用。在此，我们开发了一种紧凑的单苯分子2,5-双（（2-羟乙基）氨基）对苯二甲酸二甲酯，它很容易结晶形成两种多晶型物，A和B。多晶型物A和B都具有单苯π-体系，在晶体中呈现红色荧光。更重要的是，多晶型物A的晶体具有柔韧性，在机械力作用下可以弹性弯曲。鉴于这些优点，已在弯曲形状的多晶型物A的晶体中实现了柔性光波导，突出了其在柔性器件中的潜在应用。此外，还观察到晶体从多晶型物A到多晶型物B的热转变，同时伴随着光学性质和机械弹性的变化。
