Assessment of Begonia Extract as New Eco-friendly Inhibitor for Low-Carbon-Steel Corrosion in Acidic Environment

Abstract

Herein, Begonia obliqua (BGN) plant extract was assessed as a low-cost, green and efficient corrosion inhibitor for low-carbon steel (LCS) in 1 M HCl solution using mass loss, hydrogen evolution, electrochemical impedance spectroscopy, Tafel polarization (TP), electrochemical frequency modulation as well as surface studies by X-ray photoelectron spectroscopy (XPS), scanning electronic microscope and atomic force microscope. Increasing BGN extract dose increases the charge transfer resistance (R ct) and decreases the double-layer capacitance (C dl). The TP results showed mixed-type inhibition behavior of the studied extract with inhibition efficiency (IE) of 87.7% achieved with the addition of 300 ppm of BGN. The adsorption isotherm model of BGN extract on LCS surface followed Temkin adsorption isotherm. The inhibition mechanism of BGN was explained according to the increasing the IE with temperature and the activation parameters which suggest significant chemisorption of the BGN extract on the LCS surface. The XPS studies confirmed the formation of protective layer of BGN extract on LCS surface. Results obtained by different techniques used showed good agreement confirming the possible use of the investigated inhibitor in the industrial application.