Selective Adsorption of Dyes and Fe3+ Sensing via Tb3+ Incorporation in an Anionic Cadmium-Organic Framework

Chempluschem. 2024 Sep;89(9):e202400192. doi: 10.1002/cplu.202400192. Epub 2024 Jul 9.

Abstract

A three-dimensional (3D) anionic cadmium-organic framework, namely [(CH3)2NH2][Cd1.5(DMTDC)2] ⋅ 2DMA ⋅ 0.5H2O (Cd-MOF; DMA=N,N-dimethylacetamide), was successfully synthesized under solvothermal conditions by using a linear thienothiophene-containing dicarboxylate ligand, 3,4-dimethylthieno [2,3-b]-thiophene-2,5-dicar-boxylic acid (H2DMTDC). Single-crystal X-ray diffraction analysis reveals that Cd-MOF exhibits a 3D anionic framework with pcu α-Po topology, featuring rectangle and rhombus-shaped channels along b- and c- axis direction. Cd-MOF demonstrates selective adsorption of cationic dyes over anionic and neutral dyes. Additionally, Tb3+-loaded Cd-MOF serves as a fast-response fluorescence sensor for the sensitive detection of Fe3+ ions with a low limit of detection (8.90×10-7 M) through fluorescence quenching.

Keywords: Fe3+ Sensing; Metal-organic framework; Tb3+ encapsulation; dye adsorption and separation.