Investigation of adsorption and corrosion inhibition of mild steel in hydrochloric acid solution by 5-(4-Dimethylaminobenzylidene)rhodanine

Graphical abstract: The corrosion inhibition of mild steel in 0.5 M HCl solution by 5-(4-Dimethylaminobenzylidene)rhodanine was studied using electrochemical and scanning electron microscopy techniques. The studied organic compound has high inhibitory efficiency against mild steel corrosion in 0.5 M HCl solution. -- Highlights: •The inhibitory effect of DABRh on mild steel corrosion was studied in 0.5 M HCl. •The DABRh acts by reducing the rates of both anodic and cathodic reactions. •The inhibitor film is very stable at low anodic and cathodic overpotentials. •Langmuir adsorption isotherm exhibited the best fit to the experimental data. •The adsorption of DABRh is the mixed type of chemical and physical. -- Abstract: The adsorption and corrosion inhibition of mild steel in 0.5 M HCl solution by 5-(4-Dimethylaminobenzylidene)rhodanine (DABRh) were investigated by electrochemical and scanning electron microscopy (SEM) techniques. It was found that DABRh has high inhibitory efficiency against the corrosion of mild steel in HCl solution. This compound is classified as the mixed type corrosion inhibitor with predominant control of cathodic reaction. The high inhibitory efficiency of DABRh was related with the adsorption of DABRh molecules at the meal/solution interface and a protective film formation. The surface inhibitor film was found to be very stable at low anodic and cathodic overpotentials