The Effect of Amine-Functional Group on Heavy Metal Ion ‎Detection of a Cu-Based Metal-Organic Framework

Owing to their enriched host-guest chemistry and high porosity, metal-organic frameworks ‎‎(MOFs) applied extensively in the detection of a large variety of hazardous chemicals, ‎especially metal ions, using different instrumental methods, such as photoluminescence. In this ‎study, two pillar-layered MOFs, [Cu2(BDC)2(DABCO)] and its amine-functionalized ‎isostructure, [Cu2(NH2-BDC)2(DABCO)], were successfully prepared to highlight the amino ‎group role in the metal ions sensing via exploiting photoluminescence-based method. These ‎materials could recognize copper(II) cations efficiently by changing the luminescent response ‎in less than 20 minutes. With increasing the concentration of Cu(II) solution, first, the ‎luminescent response changes occurred intensely, then equilibrium was reached and no more ‎changes were observed. In the presence of other metal cations, the sensors almost recognized ‎the analyte selectively. At the end of the experimental tests, the reasonable mechanism of ‎sensing was proposed using FTIR spectroscopy and PXRD patterns. They confirmed that the ‎introduction of analyte does not collapse the structure, so just the chemical interaction between ‎the walls of pores and Cu(II) ions are responsible for the purposed application.‎