Mechanistic insight into the corrosion inhibition behavior of a benzimidazolic derivative on C38 steel in hydrochloric acid
Nadia Jaàfar, Said Jebbari, Mohammed H. Geesi, Abdulmalik S.A. Altamimi, Abdulaziz Alanazi, Yassine Riadi, Taibah Aldakhil, Manal A. Alossaimi, Abdelmalek Matine, Habib El Alaoui El Abdallaoui, Houssine Ait Sir, Abdellah ZeroualPurpose
This study aims to investigate the corrosion inhibition performance of the benzimidazolic derivative OSMBZ for C38 steel in 1 M HCl and to clarify its inhibition mechanism through combined experimental and theoretical approaches.
Design/methodology/approach
OSMBZ was synthesized and characterized by proton and carbon nuclear magnetic resonance spectroscopy. Its inhibition performance was evaluated using weight-loss measurements, potentiodynamic polarization, electrochemical impedance spectroscopy, SEM/EDX surface analysis, adsorption isotherm analysis, temperature-dependent measurements, density functional theory calculations and molecular dynamics adsorption simulations on the Fe(110) surface.
Findings
The inhibition efficiency increased with OSMBZ concentration, reaching 95.22% at 3 × 10–4 M and 298 K. Electrochemical results showed that OSMBZ acts as a mixed-type inhibitor with predominant cathodic influence. The adsorption process followed the Langmuir isotherm and involved both physical and chemical contributions. SEM/EDX observations confirmed the formation of a protective adsorbed layer, while theoretical calculations supported the role of molecular planarity, heteroatom-rich adsorption centers, p-conjugation and favorable interaction with the Fe(110) surface.
Originality/value
This work provides an integrated mechanistic assessment of a benzimidazolic derivative as an efficient corrosion inhibitor by correlating gravimetric, electrochemical, surface, thermodynamic, DFT and molecular dynamics results.