Corrosion Inhibition of Mild Steel in Sulfuric Acid Solution by Houttuynia Cordata Extract

The inhibition performance and mechanism of Houttuynia cordata extract (HCE) for the corrosion of mild steel in 0.5 M H2SO4 were investigated using weight loss method, electrochemical measurements and scanning electron microscope (SEM). The results revealed that HCE was an effective mixed-type inhibitor with a predominantly cathodic action for mild steel in 0.5 M H2SO4 solution, its inhibition efficiency increases with the increase of the concentration of HCE, and when the concentration of HCE reaches 0.75 g/L, the inhibition efficiency is up to 90 % at 298 K. The adsorption of HCE on steel surface obeyed Langmuir adsorption isotherm, thus the thermodynamic and kinetic parameters were calculated and discussed.