A luminescent Terbium-Succinate MOF fabricated by co-precipitation for sensing of Fe³⁺ in aqueous environment

A luminescent lanthanide coordination polymer (Ln-CP) of [Tb₂(SA)₃(H₂O)₂]·2H₂O [SA: succinic acid] has been largely prepared by co-precipitation method at room temperature. Powder X-ray diffraction (PXRD), elemental microanalysis, Fourier transform infrared spectra (FT-IR), thermogravimetric analysis (TGA) were used to confirm the composition and phase purity of the prepared powder material. The photoluminescent and sensing properties of the powders have been studied. The results show that Tb-SA powders exhibits characteristic luminescence of Tb³⁺ ion, and present the selective detection of Fe³⁺ in aqueous solution. There is an inverse correlation between the luminescent intensities and concentration of Fe³⁺ ions, which displays a linear region at low concentrations (1 × 10⁻⁵ to 8 × 10⁻⁴ M), but deviates from linearity at higher concentrations. Furthermore, the potential quenching mechanism was proposed.