Performance and interaction mechanism of a new highly efficient benzimidazole-based epoxy resin for corrosion inhibition of carbon steel in HCl: A study based on experimental and first-principles DFTB simulations

•A benzimidazole-based epoxy inhibitor is effective for C-steel corrosion in HCl.•The inhibitor protects the carbon steel surface through physicochemical adsorption.•Inhibitor-Fe(110) modeling by DFTB suggests the formation of one covalent bond.•PDOSs confirm the physicochemical interactions between BIZ epoxy and iron surface.