The inhibitive effect and adsorption behavior of ginger roots extract (GRE) on the corrosion of carbon steel in 1.0 M HCl solution at different temperatures were investigated.

The adsorption activity and inhibition effect of Eruca sativa seed extract as a green inhibitor for the dissolution of carbon steel in 1 M hydrochloric acid solution were investigated.

Metal surfaces can become damaged by corrosion when they interact with their surroundings, leading to huge financial losses. The use of corrosion inhibitors is one of the most crucial ways to combat the risky and hazardous effects of corrosion. In the present research, electrochemical techniques and surface analysis have been used to characterize the inhibition properties of (3-hydroxy-4-((4-nitrophenyl)diazenyl)-5-(phenylamino)thiophen-2-yl)(phenyl)methanone for the corrosion of carbon steel in an aerated 1.0 M HCl solution. Steel’s corrosion resistance was discovered to be improved by the presence of the examined inhibitor in 1.0 M HCl medium through the adsorption of the inhibitor species to create a barrier layer. The findings showed that when inhibitor concentrations increased and solution temperatures decreased, the inhibition performance (%IE) of the compound under study enhanced. In the light of inhibitor probe’s chemical makeup and theoretical analysis, the mechanism of the inhibition process was addressed. In a 1.0 M HCl solution containing 5 × 10⁻⁵ M of the inhibitor, the inhibition performance, at room temperature, was found to be almost 97%. The electrochemical results revealed that the examined compound successfully prevented carbon steel corrosion as a mixed-type inhibitor. The Langmuir and Freundlich isotherms are pursued by the adsorption of the examined inhibitor. Additionally, using Arrhenius and transition state equations, the activation thermodynamic parameters ΔE_a, ΔH*, and ΔS* were determined and explained. The adsorption process was illustrated using DFT computation and MC simulations. The experimental findings and theoretical simulations concurred surprisingly well. Finally, the paper presents a discussion of the inhibitory mechanism.

The performance of extract of myrrh plant as corrosion inhibitor for Cu–Zn alloy in 3.5 wt% NaCl solution polluted by 16 ppm sulfide. The results demonstrated that the corrosion rate of Cu–Zn alloy was decreased in the presence of myrrh extract.

The corrosion of iron in acidic environments has a negative impact on global industry. Herewith, the inhibitory effect of cysteine (Cys.) on mild steel (MSL) corrosion in different acidic solutions (1 M HCl, 1 M H₂SO₄, and 1 M H₃PO₄) was investigated through weight loss, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy, scanning electron microscopy (SEM), and theoretical calculations. The measurement results indicated that the adsorption of Cys. molecules on the metal surface caused corrosion inhibition. As a result, a protective layer or insoluble compound, or both, is obtained, blocking the active sites, preventing corrosion. The effectiveness (IE %) of the Cys. was enhanced by increasing concentration and lowering temperature. The maximum IE % of inhibition at 1 × 10^-2 M of Cys. obtained are 97.3, 89.7, and 84.4% in HCl, H₃PO₄, and H₂SO₄ solutions, respectively. At the same inhibitor concentration, the double-layer capacity decreased, and the charge-transfer resistance increased from 17.17 to 188.5, 3.564 to 31.91, and 1.325 to 8.715 Ω cm² in HCl, H₃PO₄, and H₂SO₄ solutions, respectively. Adsorption and PDP studies confirmed that it obeys the Langmuir adsorption isotherm and acts as a mixed-type inhibitor of physicochemical nature. The corresponding thermodynamic and kinetic parameters were also calculated and discussed. Moreover, the inhibitory effect on the surface was inspected by SEM. The findings demonstrated that the order of IE % using Cys as anticorrosion agent for MSL is HCl > H₃PO₄ > H₂SO₄ solutions.