Integrative Electrochemical and Quantum Chemical Evaluation of a Schiff Base Inhibitor for Acidic Corrosion of XC70 Steel
摘要
A Schiff base compound, designated as L3, was successfully synthesized and thoroughly analyzed through various characterization techniques, including Fourier-transform infrared (FT-IR) spectroscopy, and elemental composition analysis. Its corrosion inhibition properties for XC70 carbon steel in 1 M HCl solution were assessed using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods. The investigation examined the impact of both L3 concentration and temperature on its performance. Results indicated a direct correlation between increased concentration and temperature and improved inhibition efficiency (IE%), which reached a maximum of 84% at 10–4 M. PDP measurements revealed that L3 functions as a mixed-type inhibitor, affecting both anodic and cathodic processes. EIS data demonstrated that rising L3 concentrations enhanced the charge transfer resistance (Rct) from 104.3 to 251.2 Ω cm2, while reducing the double-layer capacitance (Cdl) from 108.6 to 63.64 µF cm–2, suggesting strong inhibitor adsorption at the metal-solution interface. Thermodynamic parameters such as