Insight into the anti-corrosion behavior of Reineckia Carnea leaves extract as an eco-friendly and high-efficiency corrosion inhibitor

This study presents an eco-friendly and high-efficiency corrosion inhibitor for carbon steel in 1 M hydrochloric acid (HCl) extracted from Reineckia carnea. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PD) were conducted to evaluate the anti-corrosion performance of Reineckia carnea extracts (RCE) for carbon steel in HCl at 298 K similar to 328 K. The RCE achieved a maximum corrosion inhibition efficiency of 95.5 % at 308 K. Fourier transform infrared spectroscopy (FTIR) and ultra-performance liquid chromatography with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) were also used on RCE to determine its main chemical composition. Furthermore, scanning electron microscopy (SEM) was utilized to observe the corrosion inhibition behavior of RCE on carbon steel on a microscopic scale. The results show that the adsorption type of RCE on carbon steel obeys the Langmuir adsorption isotherm model. The free energy Delta G(ads)(0) was calculated to be -19.85 kJ/mol based on the adsorption isotherm model, indicating that RCE is physical adsorption on the carbon steel surface. The data obtained by DFT and MD simulations are consistent with the electrochemical experimental results and demonstrate the excellent inhibition performance of RCE on carbon steel in HCl solution. This study provides valuable insight into the development of green corrosion inhibitors for carbon steel.