Investigating the Inhibitory Properties of <i>Cupressus sempervirens</i> Extract against Copper Corrosion in 0.5 M H₂SO₄: Combining Quantum (Density Functional Theory Calculation–Monte Carlo Simulation) and Electrochemical-Surface Studies

Abstract

The study investigates the potential of <i>Cupressus sempervirens</i> (EO) as a sustainable and eco-friendly inhibitor of copper corrosion in a 0.5 M sulfuric acid medium. The electrochemical impedance spectroscopy analysis shows that the effectiveness of corrosion inhibition rises with increasing inhibitor concentrations, reaching 94% with the application of 2 g/L of EO, and potentiodynamic polarization (PDP) studies reveal that EO functions as a mixed-type corrosion inhibitor. In addition, the Langmuir adsorption isotherm is an effective descriptor of its adsorption. Scanning electron microscopy/energy-dispersive X-ray spectroscopy, atomic force microscopy surface examination, and contact angle measurement indicate that EO may form a barrier layer on the metal surface. Density functional theory calculations, Monte Carlo simulation models, and the radial distribution function were also used to provide a more detailed understanding of the corrosion protection mechanism. Overall, the findings suggest that <i>Cupressus sempervirens</i> (EO) has the potential to serve as an effective and sustainable corrosion inhibitor for copper in a sulfuric acid medium, contributing to the development of green corrosion inhibitors for environmentally friendly industrial processes.