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Phytochemical-rich natural extracts have recently attracted intense attention as green corrosion inhibitors and costly benign coating components for the protection of metallic structures of immense commercial importance. Herein, various methods were applied to assess the corrosion protection efficiency of a methanolic extract of parsley (Petroselinum crispum) (PCE) on carbon steel C37 in 1 M HCl. Initially, the chemical profile of PCE was analyzed using gas chromatography/mass spectrometry (GC/MS), and myristicin and apiol were identified as the main components. The results from the weight loss, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques revealed a substantial reduction in the corrosion rate upon the use of PCE, with a maximum inhibition efficiency of 92% at 1 g L−1 PCE. To optimize the performance, the corrosion behavior was investigated over a temperature range of 303–333 K and for concentrations of 0.1–1 g L−1. The inhibition effectiveness increased at higher concentrations of PCE, whilst it decreased when the temperature was elevated. The query suggests that the adsorption process involves both physical and chemical mechanisms. The adsorption of PCE onto C37 was well described by the Langmuir adsorption isotherm. The data were used to determine the activation energy and thermodynamic parameters. The PCE coating acted as a mixed-type inhibitor, hampering both cathodic and anodic corrosion reactions. SEM further confirmed the formation of a protective coating film on the steel surface when exposed to PCE. UV-Vis and XRD were implemented to understand the inhibition mechanism and formed products at the microscopic and spectroscopic levels. Hence, the green PCE inhibitor may potentially be applied in corrosion mitigation due to its high corrosion protection efficacy and its environmentally benign nature. [ABSTRACT FROM AUTHOR]

The inhibiting impact of Mentha piperita essential oil utilized as a natural corrosion preventer for Carbon steel in 1 M hydrochloric acid solution was examined utilizing electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods, UV-visible spectra and scanning electron microscopy (SEM)/(EDS). The results of these examinations demonstrated that Mentha piperita essential oil was a significant inhibitor. The inhibition efficacy (%IE) improved with rising essential oil of Mentha piperita leaves concentration and decreasing temperature. At 100 ppm, the extract showed exceptional inhibitory action, with an efficiency of 89.6% at 303 K. According to polarization curves, the Mentha piperita essential oil functions as a mixed inhibitor, it was clarified by the carbon steel surface absorbing Mentha piperita essential oil. The adsorption process follows the Langmuir isotherm. Studies on electrochemical impedance spectroscopy revealed a single capacitive loop, demonstrating the procedure of a charge transfer was responsible for controlling the corrosion reaction. The kinetic activation and adsorption process' thermodynamic characteristics were also estimated and explained. [ABSTRACT FROM AUTHOR]

The substance Ag3SbS3 could be a viable option guaranteeing extraordinary performance for electrodes with high storage capacity, but also for solar cell absorbents. For optimal manufacturing, Ag3SbS3 thin films were electrodeposited on Fluorine-Tin Oxide (FTO) and then sulfurized at different temperatures. Structurally, XRD and RAMAN analyses confirmed that hexagonal polycrystallization of the Ag3SbS3 phase is only effective for sulfurization at 475 °C. After elaboration, the thin films were analyzed morphologically, optically and electrochemically to better define their physicochemical performances. Cyclic voltammetry (CV) analysis proved that the co-electrodeposited Ag3SbS3/FTO electrode has a pseudo-capacitor behavior in Li2CO3 (0.5 M) under the [− 700, 0 mV] potential window, developing a specific capacitance of more than 810 F/g. Furthermore, the galvanostatic charge–discharge (GCD) confirms this pseudo-capacitor behavior and that by varying the current from 1 to 5 mA, the specific energy decreases slightly from 14.5 to 11.1 Wh kg−1 to the inverse of the specific power, which varies from 175.1 to 875.3 W. k g−1. Finally, the DFT calculation executed within the framework of generalized gradient approximation (GGA) with a modified Becke-Johnson exchange–correlation potential (mBJ) predicts results extremely comparable to those discovered experimentally and which are precisely an optical gap and an absorption coefficient of the order of 105 cm−1 and 1.62 eV, respectively. All of this enabled us to conclude that Ag3SbS3 possesses the physicochemical characteristics to make it an attractive option in the disciplines of supercapacity as well as photovoltaic. [ABSTRACT FROM AUTHOR]

AbstractThe inhibition effect of N2, N6-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)pyridine-2,6-diamine (MH-PA) on the corrosion of C35E steel in 1 M HCl solution was investigated employing potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM), contact angle, X-ray photoelectron spectroscopy (XPS) methods, UV-visible spectroscopy, and theoretical calculation methods. The inhibition efficiency increased with increasing MH-PA concentration and decreased with increasing temperature, attaining 98% inhibition efficiency at 10−3M under 303K. PDP studies indicated that MH-PA is a mixed-type corrosion inhibitor and its adsorption mode conforms to Langmuir isotherm. UV-visible and FTIR spectroscopy support MH-PA adsorption over the C35E steel surface. The surface analysis through SEM, EDS, AFM, and contact angle corroborates the formation of the protective layer of MH-PA molecules on the C35E steel surface. In addition, XPS analysis revealed the formation of an N-Fe bond. Thermodynamic properties revealed that MH-PA has both physical and chemical adsorption behavior. Molecular dynamics simulations manifest that MH-PA molecules adsorb parallel to the Fe (110) surface. [ABSTRACT FROM AUTHOR]

The phytochemical compounds and the antioxidant activity of ten varieties of Phoenix dactilifera L. seeds in Morocco were examined. The phytochemical screening was used to reveal the presence of some important compounds such as polyphenols, flavonoids, tannins catechic, terpenoids, leucoanthocyanins, carotenoids, alkaloids, saponins and the absence of tanins Gallic and cardiac glycosids. The total phenolic content was ranged between 381.29±2.31 and 138.92±1.75 mg Gallic acid equivalent/g of Extract, the total flavonoid content was between 163.53±1.82 and 46.74±1.26 mg quercetin equivalent/g Extract, and tanins were found from 95.87±2.08 to 24.20±1.45 mg catechin equivalent/g Extract. Indeed, the scavenging ability with DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays recorded a low inhibitory concentration (IC50) ranged from 1.52 to 4.78 µg/mL and from 18.90 to 46.62 µg/mL respectively. Likewise, the Ferric Reducing Antioxidant Potential (FRAP) assay showed a good reduction capacity of ferric ions ranged from 69.25 to 161.26 µg/mL.

In this work, the effect of a new quinoxaline derivative, 2-phenyl-3-(prop-2-yn-1-yloxy) quinoxaline (PYQX), was evaluated as a corrosion inhibitor for carbon steel (CS) in 1 M HCl electrolyte. Weight loss measurement, atomic absorption spectroscopy, potentio­dynamic polarization, electrochemical impedance spectroscopy, scanning electron microscopy with energy dispersive spectroscopy, and UV-vis spectroscopy were employed to assess the inhibitory activity. The electronic properties of the interaction between the inhibitor molecule and the CS substrate were studied using molecular dynamics (MD) simulation, density functional theory (DFT), and Fukui functions. According to AC impedance experiments, the inhibitor under consideration showed a maximum level of 98.1 % inhibition efficiency at 1 mM and 30 °C. The Langmuir adsorption isotherm model explains the adsorption of PYQX on the CS surface. A slope of 1 denotes a strong molecule-substrate interaction, suggesting that the binding occurs at specific surface locations. To understand the functioning of the adsorption mechanism, various thermodynamic and activation parameters were evaluated. PDP tests demonstrated that PYQX functions as a mixed-type inhibitor. Computational correlations (DFT, MD, and Fukui indices) supported the experimental findings.

The novelty of the work is to scrutinize for the first time the 4R,5S- 2,4,5-tris(4-ethoxy­phenyl)-4,5-dihydro-1H-imidazole (TEPI) as a corrosion inhibitor for carbon steel (C35E) in the acidic medium. The inhibitory properties of TEPI were assessed through various methods, including electrochemical, spectroscopic, and surface analysis, as well as quantum chemical calculations. The protective effect of C35E was seen to expand as the TEPI amount was extended but to diminish as temperature was augmented, fulfilling 98.3 % at 1 mM under 303 K. Certain thermodynamic and kinetic indices were estimated and explored. The TEPI complied with the Langmuir adsorption isotherm when it adsorbs on the C35E surface. TEPI behaviour was revealed by polarization trials to be of mixed type. The establishment of an adsorption-linked preventive TEPI layer on the C35E surface has been disclosed thanks to surface analysis. The outcomes of scanning electron microscopy coupled with energy dispersive X-ray spectroscopy clearly illustrate that TEPI can effi­ci­ently adsorb at the C35E interface, substantially reducing C35E steel corrosion. UV-visible analysis of the inhibited electrolyte clearly reveals the complexation of iron cations with TEPI molecules. The density functional theory, Monte Carlo and molecular dynamic simulation were adopted to check out the adsorption characteristics of the TEPI onto C35E surface. The laboratory outcomes have been proven by DFT and MDS.