Achieving Multifunctional Detection of Th⁴⁺ and UO₂²⁺ in the Post‐Synthetically Modified Metal–Organic Framework and Application of Functional MOF Membrane

Abstract The field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln₂(NH₂‐BDC)_2.5(CH₃COO)(DMA)(H₂O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH₂‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th⁴⁺, UO₂²⁺, and Cr₂O₇²⁻, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th⁴⁺, UO₂²⁺ and Cr₂O₇²⁻) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu₂(NH₂‐BDC)_2.5(CH₃COO)(DMA)(H₂O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors.