Study of the inhibition of carbon steel corrosion by two pyridazin derivatives in 1 M HCl: Experimental study and theoretical approach✰

The assessment of the corrosion inhibitory efficacy of two novel pyridine derivatives, specifically (E)-2-(5-(2-chlorobenzyl)-6-oxo-3-styrylpyridazin-1(6H)-yl)acetic acid (CO4) and (E)-6-(4-hydroxystyryl)pyridazin-3(2H)-one (CO38), was conducted through Numerous methods, such as Potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) and Energy Dispersive X-ray (EDX) analysis, UV–visible spectroscopy, and theoretical calculations, were used to evaluate the effectiveness in preventing corrosion for carbon steel (C.S). In response to the increasing demand for environmentally friendly and biodegradable products, CO38 and CO4 inhibitors were used. Tests revealed that CO38 and CO4 inhibitory efficacy increased with concentration, reaching 96.2 % and 93.7 %, respectively. In a 1 M HCl solution, PDP investigations demonstrated that these inhibitors act as mixed-type inhibitors. Scanning electron microscopy (SEM) revealed the creation of protective layers that prevent C.S dissolution in the acid solution. These findings were supported by theoretical investigations that employed density functional theory (DFT) and molecular dynamics (MD) simulations.