Synthesis and DFT Calculation of Hg2+ Fluorescence Chemosensor Based on a New Hybrid Organic–Inorganic Nanoporous Material of SBA-Pr-Is-Hy

Abstract

In this study, a new hybrid organic–inorganic nanoporous material of SBA-Pr-Is-Hy was synthesized by modification of SBA-15 with (3-chloropropyl)triethoxysilane to get SBA-Pr-Cl, which was reacted with isatin hydrazone to obtain SBA-Pr-Is-Hy. This new compound was characterized by different FT-IR, TGA, SEM, EDX, XRD, and BET techniques. Fluorescence spectroscopy of SBA-Pr-Is-Hy was studied. According to the results, it can detect the Hg2+ ion with a detection limit of 3.5 × 10−7 M among the other metal cations. Hg2+ ion is toxic and dangerous; it is very important to identify it with simple and efficient methods. DFT calculations, including molecular electrostatic potential (MEP) surface, geometry optimization, HOMO–LUMO analysis, and quantum chemical descriptors, were investigated utilizing the B3LYP/6-311G(d,p)/LANL2DZ method. The DFT calculation verifies the experimental mechanism of interaction between the ligand and Hg2+.