Yuan Furong, Han Guanrui, Li Yunbin, Wei Wuji, He Lei, Chen Yanting, Chen Chenxin, Lan Gaoyan, Xiang Shengchang, Chen Banglin, Zhang Zhangjing
Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, 350000, China.
Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, College of Chemistry and Materials Science, Zhejiang Normal University, Jinhua, 321004, China.
Angew Chem Int Ed Engl. 2025 Jul 31:e202513288. doi: 10.1002/anie.202513288.
Flexibility is considered one of the most critical features of framework materials, playing a vital role in applications such as adsorption and separation. Hydrogen-bonded organic frameworks (HOFs) exhibit unique flexibility derived from their weak, reversible hydrogen-bonding interactions; however, realizing controlled and functional flexible behavior in HOFs remains a synthetic challenge. Herein, we report a flexible hydrogen-bonded organic framework, HOF-FJU-119, constructed from an anthracene-core, that exhibits multimode guest-responsive behavior. Upon activation, HOF-FJU-119a undergoes distinct gate-opening transformations in response to CO at 196 K and benzene vapor at room temperature. Single-crystal X-ray diffraction (SCXRD) and vapor adsorption isotherms reveal the emergence of new adsorption sites in the benzene-loaded phase, driven by strong interactions and the flexibility of C≡N⋯H─C hydrogen bonds, enabling selective benzene/cyclohexane separation. Notably, the adsorption of benzene induces a visible color change in fluorescence emission and a red shift of approximately 60 nm. Structural and density functional theory (DFT) analyses confirm increased molecular planarity, extended conjugation, and a narrowed bandgap. This work demonstrates a rare integration of selective adsorption, molecular recognition, and signal transduction within a single crystalline framework, offering a versatile platform for the development of intelligent porous materials with real-time visual tracking capabilities.
柔韧性被认为是骨架材料最关键的特性之一，在吸附和分离等应用中起着至关重要的作用。氢键有机骨架（HOFs）因其弱的、可逆的氢键相互作用而具有独特的柔韧性；然而，在HOFs中实现可控的功能性柔性行为仍然是一个合成挑战。在此，我们报道了一种由蒽核构建的柔性氢键有机骨架HOF-FJU-119，它表现出多模式客体响应行为。活化后，HOF-FJU-119a在196 K下对CO和室温下对苯蒸气发生明显的开孔转变。单晶X射线衍射（SCXRD）和气相吸附等温线表明，在苯负载相中出现了新的吸附位点，这是由强相互作用和C≡N⋯H─C氢键的柔韧性驱动的，从而实现了苯/环己烷的选择性分离。值得注意的是，苯的吸附导致荧光发射出现明显的颜色变化和大约60 nm的红移。结构和密度泛函理论（DFT）分析证实了分子平面性增加、共轭扩展和带隙变窄。这项工作展示了在单个晶体骨架中选择性吸附、分子识别和信号转导的罕见整合，为开发具有实时视觉跟踪能力的智能多孔材料提供了一个通用平台。
