Methanol Sensing by a Luminescent Zinc(II)‐Based Metal−Organic Framework

• Published in: ChemPlusChem (Weinheim, Germany) Vol. 84; no. 3; pp. 307 - 313
• Main Authors: Durini, Sara, Ilić, Nebojša, Ramazanova, Kyzgaldak, Grell, Toni, Lönnecke, Peter, Hey‐Hawkins, Evamarie
• Format: Journal Article
• Language: English
• Published: Germany 01-03-2019
• Subjects: luminescence; metal-organic frameworks; methanol; sensors; zinc; methanol; luminescence; sensors; zinc; metal-organic frameworks
• ISSN: 2192-6506; 2192-6506
• DOI: 10.1002/cplu.201900109

A luminescent zinc‐based metal‐organic framework (MOF; 1) was synthesized from a highly conjugated tridentate ligand, 1,3,5‐tris[(1E)‐2′‐(4′′‐benzoic acid)vinyl]benzene. X‐ray single crystal analysis reveals the organization of 1 in a three‐dimensional porous framework. Thermogravimetric analysis shows that 1 has a good thermal stability, and resists decomposition up to 420 °C. The removal of the solvent molecules from the cavities leads to a temporary loss of crystallinity, which can be regained by heating the MOF in diethylformamide, the solvent used for the synthesis, as shown by powder X‐ray diffraction. In addition, 1 shows luminescent features influenced by the chemical environment, making it suitable as optical sensor. Detection of methanol with a turn‐on effect was possible in low concentration in mixtures with water (50 μL/3 mL and 10 μL/3 mL) and as vapor.
A ZnII‐based metal‐organic framework containing tris[(1E)‐2′‐(4′′‐benzoic acid)vinyl]benzene shows luminescent properties, with significant change of emission intensity when suspended in different solvents. A notable turn‐on effect of the emissive features of 1 is triggered in the presence of methanol, both in a mixture with water and as vapor.