Fumed-Si-Pr-Ald-Barb as a Fluorescent Chemosensor for the Hg2+ Detection and Cr2O72− Ions: A Combined Experimental and Computational Perspective
Ghodsi Mohammadi Ziarani, Mahtab Rezakhani, Mehran Feizi‐Dehnayebi, Stoyanka Nikolova
Abstract
The surface of fumed silica nanoparticles was modified by pyridine carbaldehyde and barbituric acid to provide fumed-Si-Pr-Ald-Barb. The structure was identified and investigated through diverse techniques, such as FT-IR, EDX, Mapping, BET, XRD, SEM, and TGA. This nanocomposite was used to detect different cations and anions in a mixture of H2O:EtOH. The results showed that fumed-Si-Pr-Ald-Barb can selectively detect Hg2+ and Cr2O72− ions. The detection limits were calculated at about 5.4 × 10−3 M for Hg2+ and 3.3 × 10−3 M for Cr2O72− ions. A computational method (DFT) was applied to determine the active sites on the Pr-Ald-Barb for electrophilic and nucleophilic attacks. The HOMO-LUMO molecular orbital was calculated by B3LYP/6-311G(d,p)/LANL2DZ theoretical methods. The energy gap for the Pr-Ald-Barb and Pr-Ald-Barb+ion complexes was predicted by the EHOMO and ELUMO values. The DFT calculation confirms the suggested experimental mechanism for interacting the Pr-Ald-Barb with ions.