Multi-Technique assessment of zaleplon for corrosion control in mild steel using 1M HCl media: A study incorporating molecular dynamics, electrochemical testing, and morphological evaluation

Abstract

Background

Corrosion of mild steel in acidic environments is a significant concern, leading to material degradation and failure in several industrial applications. This study investigates the efficacy of Zaleplon as a corrosion inhibitor for mild steel in 1 M HCl media, a critical concern for the longevity and safety of steel structures.

Methods

The study employed various analytical techniques including electrochemical impedance spectroscopy, potentiodynamic polarization, and surface analysis methods such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, etc. Additionally, Density Functional Theory, Monte Carlo and Molecular Dynamics Simulations were performed to understand the interaction mechanisms at the molecular level.

Significant Findings

The results demonstrated that Zaleplon significantly enhances the corrosion resistance of mild steel. Weight loss measurements showed Zaleplon reduced mild steel corrosion rate by achieving 90.4% inhibition efficiency at 600 ppm. EIS data indicated charge transfer resistance increased from 59.88 Ω cm² (untreated) to 131.67 Ω cm² (600 ppm), with 94.57% efficiency. SEM revealed fewer corrosion pits in treated samples, and EDX confirmed higher iron content. Activation energy rose from 19.975 kJ/mol (untreated) to 49.973 kJ/mol (600 ppm). Molecular dynamics simulations showed strong Zaleplon adsorption with -226.05 kcal/mol energy, highlighting Zaleplon's potential for protecting mild steel in acidic environments.