Adsorption behavior of some green corrosion inhibitors on Fe (1 1 0) surface: The critical role of d-π interactions in binding strength

•Among the studied molecules, those with larger π–networks have greater adsorption energies at the Fe (110) surface, thus better corrosion protection efficiency.•π–back donation is found to be the dominant adsorption mechanism for the adsorption process of the studied molecules on Fe(110).•Finding highly negative adsorption energies for the molecules with π–networks in both vacuum and aggressive solutions indicates that they are potential candidates for corrosion protection of Fe.