Corrosion assessement of mild steel in acid environment using novel triazole derivative as a anti-corrosion agent: A combined experimental and quantum chemical study

Abstract The potential of a novel triazole derivative namely 4,5-diethyl 1-[(4-ethyl-2-phenyl-4,5-dihydro-1,3-oxazol-4-yl)methyl]-4,5-dihydro-1H-1,2,3-triazole-4,5-dicarboxylate (OxTDC) as anticorrosion agent for mild steel (MS) in 1 mol/L HCl solution was investigated using gravimetric and electrochemical techniques. The OxTDC was tested at various concentrations (0.001-1 mM) and four temperatures (308, 318, 328 and 338 K) to determine the optimal concentration and temperature range for the best corrosion inhibiting effect. The synthesized inhibitor showed inhibition efficiency reach to 94.8% at temperature 298 K. Corrosion current density decreased from 1071.9 µA cm−2 (blank) to 67.1 µA cm−2 at 1 mM OxTDC. This derivative acts as mixed type inhibitor and the adsorption mode conforms to Langmuir isotherm in acidic environment. Furthermore, the results elucidated from molecular simulations (DFT linked with molecular dynamics) evidenced the adsorption of OxTDC compound on the iron surface. The quantum mechanics computations clarified the electronic interactions of OxTDC molecules with metal atoms.