Controlling corrosion protection of mild steel in acidic environment via environmentally benign organic inhibitor

The current research employed electrochemical techniques to evaluate a green corrosion inhibitor Subphthalocyanine chloride (SubPc) to control the corrosion mitigation of mild steel in acidic environments. The corrosion rates and hydrogen evolution rates were measured by weight loss. The inhibitor was found to be highly effective with a corrosion-inhibiting efficiency up to 97.6% at a concentration of 150 ppm in 1 M HCl solution loaded with synthesized (SubPc) through variable concentrations. According to the obtained information from the polarization technique, the corrosion current density, icorr, decreases with increasing the concentration levels of (SubPcs) inhibitors in 1 M HCl medium. The inhibition mechanism of mild steel has been suggested as well as its excess surface charge was determined employing electrochemical impedance spectroscopy (EIS). The results suggest that the inhibitory functions by forming a protective barrier on the steel surface, hindering the corrosion process. The present study provides a new insight into developing eco-friendly and cost-effective corrosion inhibitor to protect mild steel from acidic corrosion.