Electrochemical Evaluation of Epicatechin Gallate (EG) As Corrosion Inhibitor in Bronze in a Saline Medium

Epicatechine gallate (Figure 1), isolated from green tea, has been tested as corrosion inhibitor in a bronze in a corrosive solution of 3% of NaCl and using electrochemical techniques as electrochemical impedance spectroscopy, polarization curves, and scanning electron microscopy. The results showed that 10 ppm is the best concentration to protect the metallic surface of bronze. The measurements of the different immersion times showed that the epicatechin gallate is stable for 28 days. Afterwards, the adsorption of this compound follows the Langmuir isotherm with a process of physisorption. Finally, it was proved with the use of SEM-EDS that the presence of the inhibitor film diminishes the corrosion process. Figure 1