Synthesis of fluorescent terbium-based metal-organic framework for quantitative detection of nitrite and ferric ions in water samples

Through a solvothermal reaction between the corresponding lanthanide(III) nitrate, 1,10 o-phenanthroline and pyridine 3,5-dicarboxylic acid ligands, a novel two-dimensional terbium-based metal-organic framework (Tb-MOF), named {Tb2O0.5(C12H8N2)(2)(C7H3NO4)(3)(H2O)(2.75)}(n) (1) with strong fluorescence was synthesized by hydrothermal method. The single crystal structure and phase purity of the as-synthesized Tb-MOF were verified by single crystal X-ray diffraction. Subsequently, some studies on the morphology, structure, and optical properties of the compound were carried out. The results show that the synthesized Tb-MOF (1) can be used for the fluorescence sensing of nitrite and ferric ions. Simultaneously, the as-synthesized crystal structure offers good chemical stability in different environments, such as common organic solvents, solutions with a wide pH range, and aqueous solutions of metal ions. Besides, it has good chemical stability in a certain temperature range. In addition, a detection method for nitrite and iron ions was established based on the principle of fluorescence quenching of Tb-MOF by the analytical target, showing good recovery and precision. The proposed method provides a reliable new method for detecting nitrite and ferric ions concentrations in actual water samples. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A novel two-dimensional terbium-based metal-organic framework (Tb-MOF) with strong fluorescence was synthesized through a solvothermal reaction, and its morphology, structure, and optical properties were characterized. The Tb-MOF showed fluorescence sensing capability for nitrite and ferric ions, as well as good chemical stability in different environments. Additionally, a detection method for nitrite and iron ions based on fluorescence quenching of Tb-MOF was established, providing a reliable new method for detecting their concentrations in actual water samples.