Abstract:

As a heavy metal, copper ion (Cu²⁺) plays a key role in human bodies, but excessive Cu²⁺ can induce various diseases and endanger human health. Therefore, it is important to develop new fluorescent sensors to detect Cu²⁺ rapidly and sensitively. One-dimensional chain zinc coordination polymer (Zn-CP) was successfully prepared by hydrothermal method using 1,4-bis(3,5-dicarboxy phenoxy) benzene (H₄L) as the primary ligand and 1,10-phenanthroline (phen) as the secondary ligand, which can be used as a fluorescence sensor for the efficient detection of Cu²⁺ in water. The Zn-CP possessed excellent fluorescent properties and can selectively and sensitively detect Cu²⁺ in aqueous solutions through luminescence quenching. In the range of 0—0.8×10^-6 mol/L, the Cu²⁺ concentration showed a good linear relationship with the fluorescence attenuation of the sensor and the detection limit was 1.22×10^-8 mol/L, which was lower than the limit set by the US Environmental Protection Agency (2.05×10^-5 mol/L). In addition, the quenching mechanism of Zn-CP in Cu²⁺ detection may be attributed to the formation of new chemical bonds between the coordination polymers and the Cu²⁺. This work provided a new strategy for the construction of coordination polymer-based fluorescence sensors with water-stable systems.

Key words: coordination polymers, transition metals, hydrothermal, preparation, fluorescent probes, environment

摘要：

铜离子（Cu²⁺）作为一种重金属在人体中起着关键作用，但是过量的Cu²⁺会诱发各种疾病，危害人体健康。因此，开发快速、灵敏检测Cu²⁺的新型荧光传感器非常重要。本文以1,4-双(3,5-二羧基苯氧基)苯（H₄L）为主配体，邻菲啰啉（phen）为辅配体通过水热法成功制备了一维链状锌配位聚合物（Zn-CP），可作为高效检测水中Cu²⁺的荧光传感器。该Zn-CP具有优异的荧光特性，可通过荧光猝灭作用特异、灵敏地检测水溶液中的Cu²⁺。在0~0.8×10^-6mol/L的范围内，Cu²⁺浓度与传感器的荧光衰减呈现良好的线性关系，检出限为1.22×10^-8mol/L，低于美国环境保护署规定的限值（2.05×10^-5mol/L）。此外，Zn-CP在Cu²⁺检测中的猝灭机理可归因于配位聚合物与Cu²⁺之间形成新的化学键。这项工作为构建具有水稳定系的配位聚合物类荧光传感器提供了一种新的策略。

关键词: 配位聚合物, 过渡金属, 水热, 制备, 荧光探针, 环境