In this article, an N-rich covalent organic framework (COFTFPB-TZT) was successfully synthesized using 4,4′,4′-(1,3,5-triazine-2,4,6-triyl) trianiline (TZT), and 4-[3,5-bis (4-formyl-phenyl) phenyl] benzaldehyde (TFPB). The as-prepared COFTFPB-TZT possesses irregular cotton wool patches with a large specific surface area. A novel selective electrode based on COF_TFPB-TZT was used for the determination of Mercury ions. The abundance of N atoms in COF_TFPB-TZT provides more coordination sites for Hg²⁺ adsorption, resulting in a change in the surface membrane potential of the electrode to selectively recognize Hg²⁺. Under optimal experimental conditions, the ion-selective electrode shows a good potential response to Hg²⁺, with a linear range of 1.0 × 10⁻⁹∼1.0 × 10⁻⁴, a Nernst response slope of 30.32 ± 0.2 mV/-PC at 25°C and a detection limit of 4.5 pM. At the same time, the mercury-ion electrode shows a fast response time of 10 s and good reproducibility and stability. The selectivity coefficients for Fe²⁺, Zn²⁺, As³⁺, Cr⁶⁺, Cu²⁺, Cr³⁺, Al³⁺, Pb²⁺, NH₄⁺, Ag⁺, Ba²⁺, Mg²⁺, Na⁺, and K⁺ are found to be small, indicating no interference in the detection system. The proposed method can be successfully applied to the determination of Hg²⁺ in 3 typical environmental water samples, with a recovery rate of 98.6–101.8%. In comparison with the spectrophotometric method utilizing dithizone, the proposed method is simple and fast and holds great potential application prospects in environmental water quality monitoring and other fields.

中文翻译：

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基于富氮共价有机骨架电位传感器的环境水中汞离子的快速测定

在本文中，使用 4,4',4'-(1,3,5-triazine-2,4,6-triyl) trianiline (TZT) 成功合成了富含 N 的共价有机骨架 (COFTFPB-TZT)，和 4-[3,5-双（4-甲酰基-苯基）苯基]苯甲醛（TFPB）。所制备的 COFTFPB-TZT 具有具有大比表面积的不规则棉绒斑块。基于COF _TFPB-TZT的新型选择性电极用于测定汞离子。_{COF TFPB-TZT}中丰富的N原子为Hg ²⁺的吸附提供了更多的配位位点，导致电极表面膜电位发生变化，从而选择性地识别Hg ²⁺。^{在最佳实验条件下，离子选择性电极对 Hg 2+}表现出良好的电位响应，线性范围为 1.0 × 10 ^-9 ∼1.0 × 10 ^-4，25°C 时 Nernst 响应斜率为 30.32 ± 0.2 mV/-PC，检测限为 4.5 pM。同时，汞离子电极显示出10 s的快速响应时间和良好的重现性和稳定性。^{Fe 2+} , Zn ²⁺ , As ³⁺ , Cr ⁶⁺ , Cu ²⁺ , Cr ³⁺ , Al ³⁺ , Pb ²⁺ , NH ₄ ⁺ , Ag ⁺ , Ba ²⁺ , Mg ²⁺的选择性系数、Na ⁺和 K ⁺发现很小，表明在检测系统中没有干扰。该方法可成功应用于3个典型环境水样中Hg ²⁺的测定，回收率为98.6-101.8%。与双硫腙分光光度法相比，该方法简便快捷，在环境水质监测等领域具有巨大的应用前景。