Luminescent Lead(II)-Based Coordination Polymers: Syntheses, Structures, and Their Potential Applications in Fe³⁺/Cr₂O₇^2– Detection and Anti-Counterfeiting

Luminescent coordination polymers are currently considered as potential aqueous-phase pollutant sensors and anticounterfeiting materials. In this work, two luminescent coordination polymers with a Pb(II) ion as the metal center were synthesized, displaying a three-dimensional framework structure and a two-dimensional layer structure, respectively. The compounds 1 and 2 were characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), and infrared spectroscopy (FTIR). The luminescence mechanisms of the two compounds were analyzed by first-principles calculations based on density functional theory (DFT). Their high sensitivity and selectivity in detecting Fe3+ and Cr2O72– ions in aqueous solutions were investigated, along with their excellent anti-interference ability and recyclability. Furthermore, considering the prominent luminescent visibility of compound 1, we have preliminarily explored its potential for anticounterfeiting applications.