Fujian Provincial Key Laboratory of Polymer Materials, College of Chemistry and Materials Science, Fujian Normal University, 32 Shangsan Road, Fuzhou 350007, PR China.
Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, United States.
J Am Chem Soc. 2020 Jul 15;142(28):12478-12485. doi: 10.1021/jacs.0c05277. Epub 2020 Jul 2.
A microporous three-dimensional (3D) hydrogen-bonded organic framework (HOF-20) has been constructed from an aromatic-rich tetratopic carboxylic acid, 5-(2,6-bis(4-carboxyphenyl)pyridin-4-yl)isophthalic acid (HBCPIA). The activated HOF-20a has a moderately high Brunauer-Emmett-Teller (BET) surface area of 1323 m g and excellent stability in water and HCl aqueous solution. HOF-20 exhibits highly efficient turn-up fluorescent sensing of aniline in water with a detection limit of 2.24 μM and is selective toward aniline in the presence of aromatic interferents, owing to the hydrogen bonding and edge-to-face π-π stacking interactions between the HOF-20 host and the guest aniline molecules, as demonstrated in the single-crystal X-ray structure of HOF-20⊃aniline. Density functional theory (DFT) calculations further demonstrate that the recognition of aniline molecules by HOF-20 could restrict the rotation of the aromatic rings in HBCPIA linkers, reducing the nonradiative decay pathways upon photoexcitation and subsequently enhancing the fluorescence intensity.
一种微孔三维（3D）氢键有机骨架（HOF-20）由富含芳香族的四齿羧酸 5-(2,6-双（4-羧基苯基）吡啶-4-基）间苯二甲酸（HBCPIA）构建而成。活化后的 HOF-20a 具有中等高的 Brunauer-Emmett-Teller（BET）表面积为 1323 m2/g，在水和 HCl 水溶液中具有优异的稳定性。HOF-20 对水中的苯胺表现出高效的翻转荧光传感，检测限低至 2.24 μM，并且由于 HOF-20 主体与客体苯胺分子之间的氢键和边缘对 face π-π 堆积相互作用，在存在芳香族干扰物的情况下对苯胺具有选择性，这在 HOF-20⊃苯胺的单晶 X 射线结构中得到了证明。密度泛函理论（DFT）计算进一步表明，HOF-20 对苯胺分子的识别可以限制 HBCPIA 连接体中芳环的旋转，减少光激发后的非辐射衰减途径，从而增强荧光强度。
