Lin Yuting, Zhang Jianyu, Wang Wen-Jin, Tang Zhenguo, Fang Xianying, Xu Xu, Kühn Fritz E, Zhao Zheng, Yong Qiang, Tang Ben Zhong, Cai Xu-Min
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China.
Innovation (Camb). 2025 Mar 17;6(7):100884. doi: 10.1016/j.xinn.2025.100884. eCollection 2025 Jul 7.
The aggregation process plays a significant role in regulating the aggregate structures from molecules toward macroscopic photophysical properties. Pyrene (Py), as the simplest dimer candidate, serves as a suitable model for studying the aggregation. Herein, a series of Py-based aggregation-induced emission (AIE) materials have been investigated by clarifying the comprehensive roles of oxygen, substituents, molecular motion, and packing during aggregation, initially realizing the aim of controlling aggregate structures. With a largely planar and conjugated conformation, Py shows anomalous AIE characteristics due to the oxygen quenching at the molecular level but turn-on fluorescence in the aggregate state because of the oxygen isolation. Although introducing substituents induces molecular motion and similarly weakened luminescence in the molecular state, the impact of substituents on the aggregate-state photophysical properties enormously differs, exhibiting from weak blue, strong cyan, and strong green to weak yellow emissions, due to variable aggregate structures. Interestingly, the natural alicycle-substituted Py-dehydroabietylamine (Py-DAA) exhibits both mechanochromism and acidichromism, which can be synergistically applied in dynamic encryption-decryption. This work not only elucidates the unique AIE property of Py for the first time but also clarifies the bridging role of aggregation between single-molecular and aggregate states, achieving preliminary control over the aggregate structures.
聚集过程在调控从分子到宏观光物理性质的聚集结构中起着重要作用。芘（Py）作为最简单的二聚体候选物，是研究聚集的合适模型。在此，通过阐明聚集过程中氧、取代基、分子运动和堆积的综合作用，对一系列基于芘的聚集诱导发光（AIE）材料进行了研究，初步实现了控制聚集结构的目标。芘具有很大程度的平面共轭构象，由于分子水平上的氧猝灭而表现出反常的AIE特性，但在聚集态时由于氧的隔离而开启荧光。尽管引入取代基会诱导分子运动并在分子态时同样减弱发光，但取代基对聚集态光物理性质的影响差异极大，由于聚集结构的不同，呈现出从弱蓝色、强青色、强绿色到弱黄色的发射。有趣的是，天然脂环族取代的芘 - 脱氢枞胺（Py - DAA）同时表现出机械变色和酸致变色，可协同应用于动态加密 - 解密。这项工作不仅首次阐明了芘独特的AIE性质，还阐明了聚集在单分子态和聚集态之间的桥梁作用，实现了对聚集结构的初步控制。
