PDP, EIS, and Surface Studies of the Low-Carbon Steel by the Extract of Tinospora cordifolia: A Green Approach to the Corrosion Inhibition

摘要

The influence of the Tinospora cordifolia extract on the low-carbon steel corrosion resistance in 0.5 M H_2SO_4 mediumwas investigated by using weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy measurementscoupled with surface analysis; scanning electron microscopy (SEM) and atomic force microscopy (AFM).Potentiodynamic polarization showed that the T. cordifolia extract acts as a mix-type inhibitor and 87.18% effectivenesswas observed at 500 mg/L inhibitor concentration. This extract displays significant corrosion hindrance at particularconcentrations. It is determined that the inhibition effectiveness boosts up with a rise in the concentration of theT. cordifolia extract. The adsorption nature of the T. cordifolia extract follows the Langmuir’s isotherm. Finally, theSEM and AFM analyses confirm the protection offered by the T. cordifolia extract on the steel surface in aggressivemedia.