Details

Autor(en) / Beteiligte

• Mashuga, Motsie E.
• Olasunkanmi, Lukman O.
• Ebenso, Eno E.

Titel

Experimental and theoretical investigation of the inhibitory effect of new pyridazine derivatives for the corrosion of mild steel in 1 M HCl

Ist Teil von

• Journal of molecular structure, 2017-05, Vol.1136, p.127-139

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2017

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• The effects of four pyridazine derivatives namely, 2-(6-chloropyridazin-3-yl)-2-phenylacetonitrile (P1), 3-(6-chloro-3-pyridazinyl)-1H-indole (P2), 4-(6-chloropyridazin-3-yl)benzoic acid (P3) and 3-(6-chloropyridazin-3-yl)benzoic acid (P4) on electrochemical dissolution of mild steel in 1 M HCl were studied using electrochemical, spectroscopic, and theoretical computational chemistry techniques. The inhibition efficiency increases with increasing concentration of the inhibitors and the shift in corrosion potentials obtained revealed that the compounds are mixed-type inhibitors and steel dissolution was found to be a charge transfer process with the steel/electrolyte interface showed pseudo-capacitive behaviour. P1 and P2 showed the best protection performances for mild steel in the studied medium, attributable to the presence of more nitrogen atoms and unsaturated groups in their molecules compared to P3 and P4. The experimental adsorption data obeyed the Langmuir and Temkin isotherm models and was found to involve both physisorption and chemisorption. Spectroscopic studies revealed that the inhibitor molecules interact chemically with mild steel and the pyridazine ring is actively involved in these interactions. Quantum chemical calculations also showed that pyridazine ring has the tendency of interacting with metallic atoms via both forward and backward donations. Molecular dynamic simulation revealed that the molecules can adsorb strongly onto the surface of iron in a near flat orientation. [Display omitted] •Pyridazine derivatives were studied as corrosion inhibitors.•Their corrosion inhibiting effect against steel in a 1 M HCl solution was studied.•EIS, potentiodynamic polarization methods, Monte Carlo simulation were used for analysis.•These inhibitors were adsorbed onto surfaces obeying Langmuir adsorption model.•Theoretical and experimental results were in agreement.