1, 10-phenanthroimidazole derivatives as efficient corrosion inhibitors for mild steel in 1 M HCl: synthesis, gravimetric, electrochemical and theoretical investigation

The anticorrosive performances of 1,10-phenanthroimidazole derivatives 2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline (IPB) and 1,4-di (1H-imidazo [4,54] [1,10] phenanthrolin-2-yl)benzene (DIPB) for mild steel (MS) in 1 M HCl media were surveyed via gravimetric, electrochemical and thermodynamic calculation methods. IPB and DIPB could adsorb spontaneously on the MS by two adsorption modes with predominant chemisorption, and the process obeyed Langmuir adsorption isotherm. Furthermore, IPB and DIPB were mixed-type inhibitors. Meanwhile, the UV-vis absorption spectroscopy was used to investigate the forming of complex between inhibitor and Fe. The structure-activity relationship was also discussed by means of theoretical calculation. Those results demonstrate that this type of compounds with multiple active sites exhibit great potential in corrosion inhibition of MS in acidic media. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

IPB and DIPB were studied as inhibitors for mild steel in HCl solution, showing their ability to adsorb onto the steel surface by chemisorption and form complexes with Fe, demonstrating great potential in corrosion inhibition.