Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069, P. R. China.
Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, P. R. China.
Inorg Chem. 2020 Mar 2;59(5):2833-2842. doi: 10.1021/acs.inorgchem.9b03169. Epub 2020 Feb 10.
The detection and reusage of transition-metal ions play a crucial role in human health and environmental protection. Recently, various analytical methods and substances have been successfully applied to probe or sense silver ions; however, rare representative examples have been presented regarding the simultaneous detection of silver and silver recycling with the elemental silver powder form. Herein, an unparalleled sensing mechanism for silver ions and recycling silver in its elemental form is exemplified by a fluorescent trinuclear zinc coordination cluster possessing the dual function of colorimetric sensing of silver and responding cupric ions. A Schiff-base-based trinuclear zinc coordination cluster, , with formula Zn(L)(CHCOO)(HO), has been successfully synthesized by the initial exploration of multidentate ligand HL-(()-2,4-di--butyl-6-((2-hydroxy-3-methoxybenzy-lidene)amino)phenol) with various metal ions under self-assembly reactions. Complex is highly fluorescent in solution and as a solid, in addition to acting as a fluorescence sensor toward Ag in ethanol media. Compound displays distinctive sensing of Ag through the fluorescence quenching effect at 576 nm and signal augment at 446 nm over 11 kinds of cations in the absence of interference. The proposed sensing mechanism is attributed to the ligands in which interact with Ag; the ligands undergo oxidation cyclization reaction, leading to the formation of with the formula Zn(L)(CHCOO)·2CHCHOH·HO, and Ag reduction to elemental Ag powder. Compound presents specific selectivity and sensitivity for Ag in ethanolic solution with a detection limit of 0.1722 μM. The orange color of changes to colorless during the mixing of a small amount of Ag, revealing its potential practical application in naked-eye detection of Ag. Furthermore, exhibits obvious fluorescence emission at 448 nm (λ = 380 nm) and selectively responds to Cu over 11 kinds of metal ions with the fluorescence "turn-off" owing to the formation of in ethanolic solution; it also has a detection limit of 0.0226 μM.
过渡金属离子的检测和再利用在人类健康和环境保护中起着至关重要的作用。最近，各种分析方法和物质已成功应用于探测或感测银离子；然而，很少有代表性的例子涉及以元素银粉形式同时检测银和银的回收。在此，通过具有银离子比色传感和响应铜离子双重功能的荧光三核锌配合物，举例说明了一种前所未有的银离子检测和以元素银形式回收银的传感机制。具有Schiff 碱基的三核锌配合物，[Zn(L)(CHCOO)(HO)]，通过各种金属离子在自组装反应下对多齿配体 HL-((()-2,4-二--丁基-6-((2-羟基-3-甲氧基苄叉基)氨基)苯酚)的初步探索成功合成。配合物在溶液中和作为固体时高度荧光，除了在乙醇介质中作为 Ag 的荧光传感器外。化合物在没有干扰的情况下通过在 576nm 处的荧光猝灭效应和在 446nm 处的信号增强显示出对 Ag 的独特感测，超过 11 种阳离子。所提出的传感机制归因于 中配体与 Ag 相互作用；配体发生氧化环化反应，形成具有化学式 Zn(L)(CHCOO)·2CHCHOH·HO 的，Ag 还原为元素 Ag 粉。配合物在乙醇溶液中对 Ag 具有特定的选择性和灵敏度，检测限为 0.1722μM。在少量 Ag 的混合过程中，[Zn(L)(CHCOO)]的橙色变为无色，显示出其在 Ag 肉眼检测中的潜在实际应用。此外，在乙醇溶液中，由于形成，[Zn(L)(CHCOO)]在 448nm（λ = 380nm）处表现出明显的荧光发射，并选择性地响应 Cu，超过 11 种金属离子的荧光“关闭”；它的检测限也为 0.0226μM。
