A microporous functionalized metal-organic framework as a new fluorescent probe for selective sensing of metal cations

Nowadays metal-organic frameworks with multiple luminescent centers are very fascinating as multifunctional luminescent material because of their luminescence properties, which could be systematically tuned by deliberate use of organic ligands and metal ions [1]. In this research, a two-fold interpenetration pillared-layer amine/imine-functionalized MOF known as TMU-16-NH2, [Zn2(NH2-BDC)2(4-bpdh)].3DMF, have been synthesized via a mixed ligand approach using amino-1,4-benzenedicarboxylate (NH2-BDC) and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (4-bpdh) under solvothermal condition [2]. Sensor TMU-16-NH2 exhibits Al3+-selective TURN-ON and Fe3+-selective TURN-OFF type fluorescence emission responses, for which the electrostatic interaction between Fe3+ and Al3+ ions and the inner surface of the micropores may play a critical role. Moreover, the sensor TMU-16-NH2 shows significantly color change from light yellow to orange and colorless with the addition of Fe3+ and Al3+ ions, respectively, which is distinguish by naked-eye