Stable Zr(IV)-Based Metal-Organic Frameworks with Predesigned Functionalized Ligands for Highly Selective Detection of Fe(III) Ions in Water
Stable Zr(IV)-Based Metal-Organic Frameworks with Predesigned Functionalized Ligands for Highly Selective Detection of Fe(III) Ions in Water
复制标题
稳定的 Zr(IV) 基金属有机骨架与预先设计的功能化配体，用于高选择性检测水中的 Fe(III) 离子
DOI：
10.1021/acsami.7b00918
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发表时间：
2017-03-22
影响因子：
9.5
通讯作者：
Li, Jian-Rong
中科院分区：
文献类型：
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作者：
Wang, Bin;Yang, Qi;Li, Jian-Rong
金属有机骨架材料是一类具有吸引力的荧光传感材料。提高MOFs的水解稳定性、灵敏度和功能选择性是促进MOFs在水介质中应用的关键。本工作设计并合成了两种稳定的MOFs，[Zr6O4（OH）（8）（H2O）（4）（L-1）（2）]（BUT-14）和[Zr6O4（OH）（8）（H2O）（4）（L-2）（2）]（BUT-15），用于水中金属离子的检测。用于构建MOFs的两个新配体，即5 ′，5 ″ ′-双（4-羧基苯基）-[1，1 ′：3 ′，1 ″ ″：4 ″，1 ″ ″：3 ″ ″，1 ″ ″-喹喔啉苯基]-4，4 ″ ″-二羧酸酯（L-1）和4，4 ′，4 ″，4 ″-（4，4 ′-（1，4-亚苯基）双（吡啶-6，4，2-三基））-四苯甲酸酯（L-2），在结构上相似，唯一的区别是后者被吡啶N原子官能化。这两种MOFs是同构的，具有sqc-a拓扑骨架结构，并且高度多孔，其Brunauer-Emmett-Teller（BET）表面积分别为3595和3590 m（2）g（-1）。有趣的是，它们在水中显示出强烈的荧光，这只能被痕量的Fe 3+离子淬灭。对Fe~（3+）离子的检测限分别为212和16 ppb。这种有效的荧光猝灭效应归因于Fe3+离子与这些MOFs中的配体之间的光诱导电子转移。此外，在BUT-15的配体中引入的吡啶N供体另外将其孤对电子贡献给Fe 3+离子，导致显著增强的检测能力。它也表明，BUT-15表现出不妥协的性能，用于检测Fe 3+离子在模拟生物系统。
Metal-organic frameworks are a class of attractive materials for fluorescent sensing. Improvement of hydrolytic stability, sensitivity, and selectivity of function is the key to advance application of fluorescent MOFs in aqueous media. In this work, two stable MOFs, [Zr6O4(OH)(8)(H2O)(4)(L-1)(2)] (BUT-14) and [Zr6O4(OH)(8)(H2O)(4)(L-2)(2)] (BUT-15), were designed and synthesized for the detection of metal ions in water. Two new ligands utilized for construction of the MOFs, namely, 5',5"'-bis (4-carboxypheny1)-[1,1':3',1 '':4 '',1''':3''',1''''-quinquepheny1]-4,4''''-dicarboxylate (L-1) and 4,4',4 '',4 ''-(4,4'-(1,4-phenylene)bis(pyridine-6,4,2-triy1))-tetrabenzoate (L-2), are structurally similar with the only difference being that the latter is functionalized by pyridine N atoms. The two MOFs are isostructural with a sqc-a topological framework structure, and highly porous with the Brunauer-Emmett-Teller (BET) surface areas of 3595 and 3590 m(2) g(-1), respectively. Interestingly, they show intense fluorescence in water, which can be solely quenched by trace amounts of Fe3+ ions. The detection limits toward the Fe3+ ions were calculated to be 212 and 16 ppb, respectively. The efficient fluorescent quenching effect is attributed to the photoinduced electron transfer between Fe3+ ions and the ligands in these MOFs. Moreover, the introduced pyridine N donors in the ligand of BUT-15 additionally donate their lone-pair electrons to the Fe3+ ions, leading to significantly enhanced detection ability. It is also demonstrated that BUT-15 exhibits an uncompromised performance for the detection of Fe3+ ions in a simulated biological system.