Stable Two-Fold Interpenetrated Cd(II)-MOF for Selective Dye Adsorption and Luminescence Detection of Hydroxyl-Substituted Nitroaromatic Compounds

• Published in: Crystal growth & design 2023-07, Vol.23 (7), p.5163-5172
• Main Authors: Şevik, Melike, Sezdi, Sinem Merve, Kavak, Enes, Arici, Tuğba Alp, Arici, Mürsel
• Format: Article
• Language: English
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/acs.cgd.3c00400

An anionic Cd­(II) metal–organic framework, {[NH2(CH3)2]2[Cd­(μ4-TDBAT)]·3H2O·DMF} n (1) (TDBAT: 5,5′-((thiophene-2,5-dicarbonyl)­bis­(azanediyl))­diisophthalate), was synthesized with thiophenamide-containing tetracarboxylic acid and characterized by elemental analysis, IR spectroscopy, single-crystal diffraction, powder X-ray diffraction, and thermogravimetric analysis. X-ray results showed that each Cd­(II) ion was connected to four TDBAT4– to form a 3D framework, and the charge balance of the framework was kept by dimethylamine cations. The 3D framework interpenetrated each other to form a 3D + 3D → 3D framework. Due to the anionic framework and luminescence property of 1, the dye adsorption behavior toward cationic methylene blue (MB) and luminescence sensing property toward the nitroaromatic compounds (NACs) were evaluated. The compound adsorbed the high amount (1004.12 mg g–1) of MB and could separate MB from the MB/MO mixture. Moreover, the compound displayed the detections for hydroxyl-substituted NACs (4-nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol) with detection limits of 8.14, 11.85, and 5.7 ppm, respectively, in the presence of interfering compounds. The adsorption ability of 1 toward cationic dye was assigned to predominantly electrostatic interaction and ion exchange. The possible detection mechanism for hydroxyl-substituted NACs could be attributed to competitive light absorption and hydrogen bonding interactions. The compound displayed reusability for MB adsorption and detection of hydroxyl-substituted NACs.