A theoretical and electrochemical impedance spectroscopy study of the adsorption and sensing of selected metal ions by 4-morpholino-7-nitrobenzofuran
Imen Chérif,
Bouzid Gassoumi,
Hajer Ayachi,
Mosaab Echabaane,
Maria Teresa Caccamo,
Salvatore Magazù,
Ayoub Haj Said,
Boubaker Taoufik,
Sahbi Ayachi
Affiliations
Imen Chérif
Laboratory of Physico-Chemistry of Materials (LR01ES19), Faculty of Sciences, Avenue of the Environment 5019 Monastir, University of Monastir, Tunisia; Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, Viale Ferdinando Stagno D'Alcontres No. 31, S. Agata, 98166, Messina, Italy
Bouzid Gassoumi
Laboratoire Interfaces et Matériaux Avancés (LIMA), Faculté des Sciences, Université de Monastir, Avenue de l’Environnement, 5019, Monastir, Tunisia
Hajer Ayachi
Laboratoire de Chimie Hétérocyclique, Produits Naturels et Réactivité (LR11ES39), Faculté des Sciences, Université de Monastir, Avenue de l’Environnement, 5019, Monastir, Tunisia
Mosaab Echabaane
CRMN, Centre de Recherche en Microélectronique et Nanotechnologie de Sousse, Nanomisene, LR16CRMN01, 4054, Sousse, Tunisie
Maria Teresa Caccamo
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, Viale Ferdinando Stagno D'Alcontres No. 31, S. Agata, 98166, Messina, Italy
Salvatore Magazù
Dipartimento di Scienze Matematiche e Informatiche, Scienze Fisiche e Scienze della Terra, Università di Messina, Viale Ferdinando Stagno D'Alcontres No. 31, S. Agata, 98166, Messina, Italy
Ayoub Haj Said
Laboratoire Interfaces et Matériaux Avancés (LIMA), Faculté des Sciences, Université de Monastir, Avenue de l’Environnement, 5019, Monastir, Tunisia
Boubaker Taoufik
Laboratoire de Chimie Hétérocyclique, Produits Naturels et Réactivité (LR11ES39), Faculté des Sciences, Université de Monastir, Avenue de l’Environnement, 5019, Monastir, Tunisia
Sahbi Ayachi
Laboratory of Physico-Chemistry of Materials (LR01ES19), Faculty of Sciences, Avenue of the Environment 5019 Monastir, University of Monastir, Tunisia; Corresponding author.
The selectivity of a novel chemosensor, based on a modified nitrobenzofurazan referred to as NBD-Morph, has been investigated for the detection of heavy metal cations (Co2+, Pb2+, Mg2+, Ag+, Cu2+, Hg2+, Ni2+, and Zn2+). The ligand, 4-morpholino-7-nitrobenzofurazan (NBD-Morph), was characterized using spectroscopic techniques including FT-IR and 1H NMR. Vibrational frequencies obtained from FT-IR and proton NMR (1H) chemical shifts were accurately predicted employing the density functional theory (DFT) at the B3LYP level of theory. Furthermore, an examination of the structural, electronic, and quantum chemical properties was conducted and discussed. DFT calculations were employed to explore the complex formation ability of the NBD-Morph ligand with Co2+, Pb2+, Mg2+, Ag+, Cu2+, Hg2+, Ni2+, and Zn2+ metal cations. The comparison of adsorption energies for all possible conformations reveals that NBD-Morph exhibits sensitivity and selectivity towards metal ions, including Pb2+, Cu2+, Ag+, and Ni2+. However, an assessment of their reactivity using QTAIM topological parameters demonstrated the ligand's greater complexation ability toward Cu2+ or Ni2+ than those formed by Pb2+ or Ag+. Additionally, molecular electrostatic potential (MEP), Hirshfeld surfaces, and their associated 2D-fingerprint plots were applied to a detailed study of the inter-molecular interactions in NBD-Morph-X (X = Pb2+, Cu2+, Ag+, Ni2+) complexes. The electron localization function (ELF) and the localized-orbital locator (LOL) were generated to investigate the charge transfer and donor-acceptor interactions within the complexes. Electrochemical analysis further corroborates the theoretical findings, supporting the prediction of NBD-Morph's sensory ability towards Ni2+ metal cations. In conclusion, NBD-Morph stands out as a promising sensor for Ni2+.
