Liao Rui, Wang Xiumei, Peng Ling, Sun Huibin, Huang Wei
China Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), Jiangsu National Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, P.R. China.
Shaanxi Institute of Flexible Electronics (SIFE), Northwestern Polytechnical University (NPU), 127 West Youyi Road, Xi'an 710072, China.
ACS Appl Mater Interfaces. 2021 Jun 16;13(23):27491-27499. doi: 10.1021/acsami.1c07252. Epub 2021 Jun 7.
Organic smart fluorophores (OSFs) are highly desirable over the past decades because of their potential applications in advanced photonic devices. However, it is still difficult and challenging to obtain such materials with tunable photophysical properties and high emission efficiency based on robust construction strategies. Therefore, we proposed a simple and efficient strategy for constructing OSFs by balancing the competition between intermolecular interactions and external stimuli via molecular structure design. In this work, four pyrene derivatives (, , , and ) with tunable stimuli-responsive properties were designed and synthesized. The tunable intermolecular interactions in solution states were successfully demonstrated by the molecular structure and solution concentration-dependent luminescence properties. The effect of alkyl chain length on molecular packing in solid states was investigated by polarized optical microscopy and powder and single-crystal X-ray diffraction; the results show that with the increase in molecular chain length, the molecular packing of the compounds gradually changed from π-π stacked compact mode to X-crossing stacked loose mode, which leads to different stimuli-responsive phenomena of these compounds. The strategy provided herein facilitates the construction of multistimuli-responsive (thermochromism, mechanochromism, and vapochromism) OSFs with adjustable emission color. Harnessing the heat-responsive luminescence properties and great solubility of , the optical information anticounterfeiting based on temperature was demonstrated by printing different concentrations of solution on filter papers. Much more, this research may provide broad implications for the design of organic smart materials based on intermolecular interactions.
在过去几十年里，有机智能荧光团（OSFs）因其在先进光子器件中的潜在应用而备受青睐。然而，基于稳健的构建策略来获得具有可调光物理性质和高发射效率的此类材料仍然困难且具有挑战性。因此，我们提出了一种简单有效的策略，通过分子结构设计来平衡分子间相互作用与外部刺激之间的竞争，从而构建有机智能荧光团。在这项工作中，设计并合成了四种具有可调刺激响应特性的芘衍生物（、、、）。通过分子结构和溶液浓度依赖性发光性质成功证明了溶液状态下可调的分子间相互作用。利用偏光显微镜以及粉末和单晶X射线衍射研究了烷基链长度对固态分子堆积的影响；结果表明，随着分子链长度的增加，化合物的分子堆积逐渐从π - π堆积紧密模式转变为X交叉堆积松散模式，这导致了这些化合物不同的刺激响应现象。本文提供的策略有助于构建具有可调发射颜色的多刺激响应（热致变色、机械变色和气相变色）有机智能荧光团。利用的热响应发光特性和良好的溶解性，通过在滤纸上打印不同浓度的溶液展示了基于温度的光学信息防伪。此外，这项研究可能为基于分子间相互作用的有机智能材料设计提供广泛的启示。
