Acridine-based thiosemicarbazones as novel inhibitors of mild steel corrosion in 1 M HCl: synthesis, electrochemical, DFT and Monte Carlo simulation studies.

Autor: Akpan ED; Department of Chemistry, Faculty of Natural and Agricultural Sciences, North-West University Private Bag X2046 Mmabatho 2735 South Africa Eno.Ebenso@nwu.ac.za.; Material Science Innovation & Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University Private Bag X2046 Mmabatho 2735 South Africa., Isaac IO; Department of Chemistry, Faculty of Natural and Applied Sciences, Akwa Ibom State University Ikot Akpaden Akwa Ibom State Nigeria., Olasunkanmi LO; Department of Chemistry, Faculty of Natural and Agricultural Sciences, North-West University Private Bag X2046 Mmabatho 2735 South Africa Eno.Ebenso@nwu.ac.za.; Material Science Innovation & Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University Private Bag X2046 Mmabatho 2735 South Africa.; Department of Chemistry, Faculty of Science, Obafemi Awolowo University Ile-Ife 220005 Nigeria., Ebenso EE; Department of Chemistry, Faculty of Natural and Agricultural Sciences, North-West University Private Bag X2046 Mmabatho 2735 South Africa Eno.Ebenso@nwu.ac.za.; Material Science Innovation & Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University Private Bag X2046 Mmabatho 2735 South Africa., Sherif EM; Center of Excellence for Research in Engineering Materials (CEREM), King Saud University P. O. Box 800 Al-Riyadh 11421 Saudi Arabia.; Electrochemistry and Corrosion Laboratory, Department of Physical Chemistry, National Research Centre El-Behoth St. 33, Dokki Cairo 12622 Egypt.
Jazyk: angličtina
Zdroj: RSC advances [RSC Adv] 2019 Sep 18; Vol. 9 (51), pp. 29590-29599. Date of Electronic Publication: 2019 Sep 18 (Print Publication: 2019).
DOI: 10.1039/c9ra04778f
Abstrakt: Electrochemical, surface morphology, density functional theory and Monte Carlo simulation methods were employed in investigating the effects of (2 E ,2' E )-2,2'-(3,3,6,6-tetramethyl-9-phenyl-3,4,6,7-tetrahydroacridine-1,8(2 H ,5 H ,9 H ,10 H )-diylidene)bis( N -phenylhydrazinecarbothioamide) (IAB-NP), (2 E ,2' E )-2,2'-(3,3,6,6-tetramethyl-9-phenyl-3,4,6,7-tetrahydroacridine-1,8(2 H ,5 H ,9 H ,10 H )-diylidene)bis( N -(2,4-difluorophenyl)hydrazinecarbothioamide)IAB-ND) and (2 E ,2' E )-2,2'-(3,3,6,6-tetramethyl-9-phenyl-3,4,6,7-tetrahydroacridine-1,8(2 H ,5 H ,9 H ,10 H )-diylidene)bis( N -(2-fluorophenyl) hydrazinecarbothioamide) (IAB-NF) on mild steel corrosion in 1 M HCl solution. From the studies, compounds IAB-NP, IAB-ND and IAB-NF inhibit mild steel corrosion in the acid and the protection efficiencies were found to increase with the increase in concentration of each compound. At the optimum inhibitor concentration of 1.5 × 10 -4 M, the inhibition efficiencies (%) of the compounds are in the order IAB-NF (90.48) > IAB-ND (87.48) > IAB-NP (85.28). Potentiodynamic polarization measurements revealed that all the compounds acted as mixed-type corrosion inhibitors. Experimental data for the adsorption of the studied molecules on a mild steel surface in 1 M HCl fitted into the Langmuir adsorption isotherm and the standard free energies of adsorption (Δ G o ads ) suggested both physisorption and chemisorption mechanisms. Scanning electron microscopy analyses confirmed the formation of a protective film on the mild steel surface by the inhibitor molecules, resulting in protection of the metal from corrosive electrolyte ions. The experimental findings were corroborated by both theoretical density functional theory and Monte Carlo simulation studies.
Competing Interests: There are no conflicts to declare.
(This journal is © The Royal Society of Chemistry.)
Databáze: MEDLINE
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