Wang Jun, Wang Jiande, Qiao Shujie, Guo Zhiyong
College of Materials Science and Engineering, Fuzhou University, Fuzhou, Fujian, 350108, P. R. China.
Chemistry. 2024 Jun 25;30(36):e202401044. doi: 10.1002/chem.202401044. Epub 2024 May 17.
Covalent organic frameworks (COFs) with ordered π structures are very promising in porous light-emitting materials. However, most of these COFs are either poor in luminescence or lack of water-stability. Herein, a series of isostructural D-A vinylene-linked COFs were constructed based a new D symmetric linker 1,4-bis(4,6-dimethyl-1,3,5-triazin-2-yl)benzene (TMTA) with high crystallinity, comparative high surface area and excellent chemical/thermal stability. Impressively, their adsorption and luminescence wavelength vary with respect to the density of π-systems in the electron-donating group, which constitute the foundation for molecular engineering the luminescent properties of vinylene-linked COFs. The DFT calculations further established the relationship between the luminescence properties and the donor electronic structure. Moreover, one of representative COF named FZU-203 showed inspiring applications in bioimaging, which may further provide strategic guidance for the use of vinylene-linked COFs as fluorescent nanoprobes in non-invasive medical diagnosis and visualization therapy of tumors.
具有有序π结构的共价有机框架（COFs）在多孔发光材料方面极具前景。然而，这些COFs大多发光性能不佳或缺乏水稳定性。在此，基于一种新型D对称连接体1,4-双（4,6-二甲基-1,3,5-三嗪-2-基）苯（TMTA）构建了一系列同构的D-A亚乙烯基连接的COFs，其具有高结晶度、较高的比表面积以及优异的化学/热稳定性。令人印象深刻的是，它们的吸附和发光波长随供电子基团中π体系的密度而变化，这为分子工程调控亚乙烯基连接的COFs的发光性能奠定了基础。DFT计算进一步确立了发光性能与供体电子结构之间的关系。此外，一种名为FZU-203的代表性COF在生物成像中展现出令人振奋的应用，这可能进一步为将亚乙烯基连接的COFs用作荧光纳米探针用于肿瘤的非侵入性医学诊断和可视化治疗提供战略指导。
