DFT/molecular scale, MD simulation and assessment of the eco-friendly anti-corrosion performance of a novel Schiff base on XC38 carbon steel in acidic medium

The 2-furaldehyde semicarbazone (FSC), an environmentally safe Schiff base, has been synthesized and tested for the first time as a corrosion inhibitor for XC38 carbon steel in an acidic environment. This compound's anti-corrosion properties are assessed using electrochemical, analytical, and characterization techniques. At 293 K and an FSC concentration of 500 ppm, the inhibitory effectiveness increased with the FSC concentration, reaching a maximum of around 91.5%. Furthermore, an increase in temperature from 303 to 323 K increased the corrosion rate, most likely due to the inhibitor agent's desorption from the steel surface. Scanning Electron Microscope (SEM) and X-ray Fluorescence (XRF) metal surface examination revealed that the presence of FSC causes the development of a protective layer. FSC adsorption isotherms on carbon steel were measured at different temperatures, displaying an exothermic behavior that corroborated the earlier observations. Electrochemical experiments show that as the inhibitor concentration increases from 50 to 500 ppm, I-corr decreases from 0.695 to 0.123 mAcm(-2). At the same time, the maximum change in E-corr values is 23.1 mV, leading to the conclusion that this Schiff base (inhibitor) is a mixed type of (anodic/cathodic) inhibitor. The FSC Electrophilic/nucleophilic attacks on carbon steel are theoretically studied. MD simulations revealed the FSC molecules' adsorption process on the steel surface. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

2-Furaldehyde semicarbazone (FSC) has been synthesized and tested as a corrosion inhibitor for XC38 carbon steel in an acidic environment for the first time, showing promising anti-corrosion properties. The inhibitory effectiveness of FSC increases with concentration, forming a protective layer on the steel surface. Moreover, temperature rise can lead to higher corrosion rates, and FSC acts as a mixed type inhibitor, functioning at both the anodic and cathodic sites.