Molecular Reactivity and Adsorption Behavior of Quercetin-Based Compounds on Aluminum: Insights from DFT and Simulation

When aluminum is exposed to moisture and oxygen, it undergoes electrochemical breakdown known as corrosion, which results in the metal becoming white and chalky aluminum oxide or hydroxide. Using density functional theory (DFT) and molecular dynamics simulations, this work examines the corrosion inhibition of two organic compounds on aluminum: quercetin (QU) and ۳,۵-dimethoxyquercetin (MR). To assess the electronic characteristics controlling inhibitor–metal interactions, quantum chemical parameters were calculated. The QU has a lower energy gap (۲۲۴.۷ kJ/mol) and a larger HOMO energy (−۵۲۲.۹ kJ/mol) than MR findings show, suggesting a greater propensity for electron donation and increased chemical reactivity. The fact that QU is more reactive and more appropriate for adsorption on the aluminum surface is further supported by global softness and ionization potential. Oxygen atoms were shown to be the primary reactive sites for both electrophilic and nucleophilic attacks by Fukui function analysis, emphasizing their function in coordinating with the metal surface. QU has a much greater adsorption energy (−۲۳۷.۱۰۸ kJ/mol) than MR (−۹۴.۳۴۱۳ kJ/mol), suggesting a stronger and more stable contact, according to adsorption experiments employing Forcite quench dynamics on the Al (۱۱۰) surface. The creation of a compact protective layer that successfully blocks active corrosion sites is suggested by the high binding energy of QU. MR, on the other hand, has reduced inhibitory effectiveness and poorer adsorption. The combined theoretical findings show that QU's better electrical characteristics and adsorption behavior make it a more potent corrosion inhibitor.

کلیدواژه ها:

Corrosion Inhibition ، Density functional theory ، aluminum surface ، Adsorption energy ، Quantum chemical parameters