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This article is part of the contribution to the development of two medicinal plants widely used by the Moroccan population: white wormwood (Artemisia herba-alba) andArâr (Juniperus phoenicea), species belonging to the Asteraceae and Cupressaceae families, respectively. The present work was conducted to investigate the chemical composition and anticorrosive properties of essential oils (EOs) extracted from these plants. The chemical analysis of the essential oils (EOs) was carried out by GC-MS/MS. Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and quantum chemical calculations by density-functional theory at B3lYP were used to study the anticorrosive effect of the researched oils on mild steel in 1 M hydrochloric acid solution. Moreover, SEM-EDX analysis was used to identify the surface morphology of mild steel surface. GC-MSMS results showed the presence of 32 potentially active compounds in the EOs of Artemisia herba-alba. The average yield of the EOs was about 1.39 ± 0.17 mL/100 g dry matter. Beta thujone (30.07%) and alpha thujone (13.32%) are the main components, while for the EOs of Juniperus phoenicea, the study showed the presence of 30 constituents, with alpha-pinene (43.61%) and manoyl oxide (11.5%) as the main components. The average yield of HE was 1.10 ± 0.03 mL/100 g dry matter. The findings demonstrated an important anticorrosive action of EOs from Artemisia herba-alba and Juniperus phoenicea. Notably, the experimental results showed good efficiency of the studied essential oils and correlated well with the density-functional theory (DFT) calculations. The results of potentiodynamic polarization measurements showed that hydrazone acted as a mixed-type inhibitor. The EIS results showed an increase in charge transfer resistance accompanied by a noticeable decrease in Cdl values, revealing that both studied oils were effective as reliable inhibitors for the protection of mild steel in 1 M HCl solution. Also, the efficiency decreased with decreasing inhibitor concentrations. Surface studies ensure the effectiveness of both investigated oils and the reduction of the surface roughness of mild steel. Furthermore, DFT results of the major constituents of Artemisia herba-alba and Juniperus phoenicea EOs revealed insights into the chemical reactivity of the tested oils while supporting the experimental conclusions and showed outstanding adsorption ability of both investigated EOs on the steel surface.

In this book chapter, the authors focus on the comparative study of some benzimidazole-substituted compounds used as corrosion inhibitors for mild steel in molar Hydrochloric acid solution. It has been determined that the quinazolinone studied compounds exhibit a very good performance as corrosion inhibitors for mild steel in molar Hydrochloric acid solution, as the halogen-substituted compounds show better inhibitive performance than the non-halogen-substituted one. Correspondence between inhibition property, molecular structure, and halogen substitution of benzimidazole-substituted compounds is investigated, using chemical, electrochemical, and theoretical methods. Halogen substitution effect on the inhibition performance has also been explored by quantum chemical computations and obvious correlations were observed. The binding energies of tested compounds on Fe(110) surfaces were calculated using Monte Carlo simulation. Bromide-substituted compound shows better inhibitive performance than the chloride-substituted one.

The use of organic compounds as corrosion inhibitors is one of the effective and economical methods to reduce corrosive attacks on metallic materials. In this work, the inhibition ability of two benzimidazole derivatives (SHA and BBC) against the corrosion of mild steel in Phosphoric acid solution was studied using electrochemical techniques, Scanning Electron Microscopy, Energy dispersive X-ray analysis, and Density Functional Theory method. The Potentiodynamic Polarization measurements indicate that the synthesized inhibitors are effective mixed-type inhibitors. SEM/EDX analysis strongly supports the obtained results and confirms the existence of barrier film on the metal surface.

The development of green corrosion inhibitors is a challenging task as it has to comply with strict environmental regulations. Ionic liquids (ILs) have recently been proposed as promising corrosion inhibitors. The present paper reports on two ILs designed to act as green and efficient high-temperature corrosion inhibitors. The prepared ILs, namely, choline formate (ChF) and choline acetate (ChA), are composed of biologically active ions. To elucidate their structure and corrosion inhibition effect on mild steel in 5% HCl the ILs were subjected to characterization tests like proton nuclear magnetic resonance (

This study aims at the valorization of Taxus baccata (L.) in corrosion inhibition. The effect of the extract on corrosion inhibition of mild steel in 1.0 M HCl solution by weight loss measurements, potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) showed that Taxus baccata (L.) leaves extract is a good corrosion inhibitor with an inhibition efficiency of 98%, 96% and 95% at the concentration of 1.0 g/L respectively. Polarisation curves indicated that the extract acted as a mixed type inhibitor. The adsorption on the mild steel surface obeyed the Langmuir isotherm. The activation energy values ∆G0ads (-29.61 KJ.mol-1) confirmed the physical adsorption process of this inhibitor. The study of adsorption kinetics showed a maximum inhibitory efficiency of 90.5 % after one hour of immersion time. Scanning electron microscopy revealed the formation of a protective layer on the steel surface. Analysis of the extract by gas chromatography revealed the dominance of Diisooctyl phthalate (17.22%), Bicyclo [4.4.0] dec-2-ene-4-ol,2-methyl-9-(prop-1-en-3-ol-2-yl) (16.43%), Methanesulfonic acid,4-oxoadamantan-2-yl ester (8.75%), Diethyl phthalate (8. 31 %), The structural and electronic properties of the main components of this extract were calculated using DFT to better understand the adsorption behaviour and inhibition mechanism of this plant.

It is well known that, surfactants provide a neutral, positive and/or negative charge on the electrode surface by forming a monolayer, which in turn affects the charge transfer and redox potential during the electroanalysis process. However, the molecular level understanding of these surfactant-modified electrodes is worth investigating because the interaction of the analyte with the electrode surface is still unclear. In this report, we used quantum chemical models based on computational density functional theory (DFT) to investigate the polysorbate 80 structure as well as the locations of energy levels and electron transfer sites. Later, the bare carbon paste electrode (bare/CPE) was modified with polysorbate 80 and used to resolve the overlapped oxidation signals of dihydroxy benzene isomers. The m/n values obtained at polysorbate/CPE was approximately equal to 1, signifying the transfer of same number of protons and electrons. Moreover, the analytical applicability of the modified electrode for the determination of catechol (CC) and hydroquinone (HQ) in tap water samples gave an acceptable recovery result. Overall, the application of DFT to understand the molecular level interaction of modifiers for sensing applications laid a new foundation for fabricating electrochemical sensors.

An ethnobotanical survey was conducted among herbalists in the north-central region of Morocco using a questionnaire in order to highlight knowledge and know-how and to establish an inventory of herbal remedies used in the treatment of diseases common in the region and rarely cited in the bibliography: in this case, it is insomnia, asthenia, and oral-gum infections. The results showed that 120 herbalists were interviewed in different areas of the Fez-Meknes region, about 86 species were cited and grouped into 60 families (47 plants to treat asthenia, 25 to treat insomnia, and 21 to treat oral and gum infections). The reported plants have been identified and presented with the binomial name, family, part used, and method of preparation. In addition, the versatility was observed in several plants, indicating that the same plant could be used to treat conditions of different groups. Herbalists are people of both sexes belonging to different age groups and have different socioeconomic and intellectual levels. Eighty percent of surveyed herbalists are willing to provide us information about plants in the studied area. The most cited plants for treating these diseases are Lavandula dentata, Matricaria chamomilla, Rosmarinus officinalis, Allium cepa, Origanum vulgare, Origanum majorana, Marrubium vulgare, Lepidium sativum, and Ocimum basilicum. The Lamiaceae are the most quoted family. The leaves are the most commonly used organs. Infusion is the most common form of preparation. The results of this ethnobotanical study could constitute an important source of information and databases for further research in the fields of phytochemistry and pharmacology in order to find new bioactive molecules. In addition, this document can be used in the protection of indigenous knowledge.