Understanding imidazole derivatives effect as a corrosion inhibitor for brass in nitric acid: a combined experimental and theoretical assessments

Abstract

ABSTRACT This paper presents a new study on imidazole derivatives namely 1H-imidazole (IM), N-methylimidazole (MIM) and 1H-benzimidazole (BIM) as a corrosion inhibitor for brass in nitric acid medium. Electrochemical results demonstrate that the inhibition increases with a high concentration of imidazole derivatives; the inhibitory efficiency reaches a maximum of 94% at 10–2 mol L−1 for BIM. SEM morphology and EDS analysis show that these derivatives are adsorbed onto the brass interface, the brass sample is effectively protected and the surface becomes relatively flat, which is more significant in the presence of 1H-benzimidazole. FTIR results confirm the retention of BIM on the interface of Cu-Zn alloys. In addition, quantum chemistry calculation manifests that the three derivatives can reveal high anticorrosion properties. Molecular dynamics simulation data manifest that the three imidazole derivatives can be adsorbed at the brass surface in a paralleled way, and have large binding energy. Highlights A new action of imidazole derivatives to mitigate brass corrosion was explored in HNO3. BIM showed inhibitory efficiency more than 94% in HNO3 solution. The inhibition mechanism is studied using SEM/EDS surface analysis and FTIR analysis. The calculated adsorption energies are ranked in the following order: BIM > MIM > IM. Theoretical and experimental results lead to used imidazole derivatives as potential corrosion inhibition for brass in solution. GRAPHICAL ABSTRACT