Inhibition effect of bamboo leaves extract on cold rolled steel in Cl3CCOOH solution

Abstract

The corrosion inhibition by Dendrocalamus brandisii leaves extract (DBLE)/major flavonoid of cold rolled steel (CRS) in trichloroacetic acid (Cl3CCOOH) solution was investigated by weight loss, electrochemical techniques and atomic force microscope (AFM). The adsorption mode of four major compounds (rutin, vientin, isovientin and orientin) on Fe (001) surface was theoretically investigated by molecular dynamics (MD). The results show that DBLE is a good inhibitor, and the maximum inhibition efficiency is higher than 95%. The adsorption of DBLE on CRS surface obeys Langmuir isotherm with exothermic process. DBLE behaves as a mixed inhibitor. AFM results confirm that DBLE could retard the corrosion of CRS in Cl3CCOOH. The inhibitive action of each flavonoid is lower than DBLE, and follows the order: rutin>vientin>isovientin>orientin. The major flavonoids in DBLE are adsorbed onto Fe (001) surface through FBS (flavones backbone structure) with a nearby flat orientation.