Glutenin as an Efficient Green Inhibitor for HPB300 Steel in Simulated Concrete Pore Solution Containing 3 wt % NaCl: Experiments and Computational Investigations

This study evaluated the corrosion inhibition performance of glutenin for HPB300 steel in a simulated concrete pore solution containing 3 wt % NaCl. Electrochemical techniques (PDP and EIS) quantified inhibition efficiency, while SEM, XPS, and FTIR spectroscopy characterized the morphology and chemistry of the interfacial film. Molecular dynamics combined with quantum chemical calculations elucidated adsorption mechanisms at the atomic scale. Experimental results revealed that 1.0 g/L glutenin achieved an inhibition efficiency of 94.46%, higher than those of most reported green inhibitors. Adsorption obeyed the Langmuir isotherm. An increased Fe²⁺/Fe³⁺ ratio was observed. The principal amino acids adsorbed on Fe(110) with negative adsorption energies and anchored via -NH₂, -COOH, and a pyrrole ring; the adsorption strength follows glutamic acid > proline > leucine. Overall, using multiscale testing and analysis, this study elucidates the mechanism by which glutenin retards the corrosion rate and supports its innovative application as a sustainable corrosion inhibitor.