DFT Investigation of Antidepressant drug Adsorption on Graphene Oxide Nanosheets: A Computational Approach for Pharmaceutical Pollutant Removal

Antidepressant pharmaceuticals, particularly fluoxetine, represent emerging environmental contaminants detected in water resources worldwide. Efficient removal strategies are essential due to their persistence and bioactivity. Density Functional Theory (DFT) calculations at B۳LYP/۶-۳۱G(d,p) level were employed to investigate fluoxetine adsorption onto graphene oxide (GO) nanosheet. Geometric optimization, frontier molecular orbital (FMO) analysis, molecular electrostatic potential (MEP) mapping, natural bond orbital (NBO) analysis, and density of states (DOS) calculations were performed to elucidate interaction mechanisms. Exothermic adsorption (negative Ead) confirmed stable non-covalent interactions via hydrogen bonding (CH). NBO analysis revealed charge transfer from drug oxygen lone pairs to GO framework. Reduced HOMO-LUMO gap (۰.۵۵۱ eV) and increased dipole moment (۱.۹۷۶۷ D) indicated enhanced reactivity. MEP surfaces identified electron-rich oxygen sites as primary interaction centers. Graphene oxide demonstrates excellent potential as a nanoadsorbent for fluoxetine removal from aqueous environments through chemisorption, offering insights for developing efficient water treatment technologies.

کلیدواژه ها:

fluoxetine ، graphene oxide (GO) ، nanoadsorbent ، DFT