Corrosion Inhibition Efficiency Research Articles

Seaweed extract as green corrosion inhibitor for carbon steel in hydrochloric acid solution

This study aimed to investigate the corrosion inhibition effect of seaweed extract abbreviated as SAE on carbon steel (CS) in 1.0 mol/L hydrochloric acid (HCl) solution. The functional groups in SAE were characterized using Fourier transform infrared (FTIR) spectroscopy. The corrosion inhibition effect of SAE on CS was determined through weight loss experiments, electrochemical tests, and scanning electron microscopy (SEM). Additionally, the composition of the corroded CS surface after immersion in SAE solution was measured through X-ray photoelectron spectroscopy (XPS) analysis. The results indicate that SAE achieves a corrosion inhibition efficiency of 95.0 % for CS in 1.0 mol/L HCl. Furthermore, SAE was identified as a mixed-type inhibitor. The adsorption of SAE on the CS surface follows the Langmuir adsorption isotherm model. UV–visible spectroscopy (UV–vis) studies confirmed that the corrosion inhibition of CS was achieved through the formation of CS-SAE phytoconstituents complex. Moreover, Molecular dynamics simulations (MS) and quantum chemical (QC) calculations were utilized to predict the adsorption properties of several major SAE components and the chemical parameters associated with inhibitory efficiency. This work offers insightful information for developing and applying eco-friendly CI for acid pickling or rust removal from CS.

XGBoost performance in predicting corrosion inhibition efficiency of Benzimidazole Compounds

In this study, we compare the performance of the XGBoost model with a Support Vector Machine (SVM) model from the literature in predicting a given task. Performance metrics such as the coefficient of determination (R2), root mean squared error (RMSE), and mean absolute error (MAE) were utilized to evaluate and compare the models. The XGBoost model achieved an R² of 0.99, an RMSE of 2.54, and an MAE of 1.96, significantly outperforming the SVM model, which recorded an R² of 0.96 and an RMSE of 6.79. The scatter plot for the XGBoost model further illustrated its superior performance, showing a tight clustering of points around the ideal line (y = x), indicating high accuracy and low prediction errors. These findings suggest that the XGBoost model is highly effective for the given prediction task, likely due to its ability to capture complex patterns and interactions within the data.

Grafted sepiolite as smart nanocontainer for Daphne Gnidium plant extract: PH-dependent controlled release and effective green anti-corrosion coating

This study focuses on advancing the development of environmentally sustainable and efficient active anti-corrosion coatings for metal substrates in various engineering applications. A novel smart anti-corrosive container was developed using fibrous sepiolite clay (Sep). Sep was first subjected to grafting with 3-Aminopropyl-diethoxy-methylsilane (APDEMS). Subsequently, the grafted-Sep (Sep-G) was used to load a Daphne Gnidium plant extract (DGE) as a natural corrosion inhibitor. The modification process of Sep was carefully monitored and characterized through Zeta potential, scanning electron microscopy, X-ray diffraction, UV/visible spectroscopy, and Fourier transform infrared spectroscopy. The results highlighted the successful clay modification with a silane loading of 7.68 % and a DGE adsorbed amount of approximately 58 mg/g. The DGE release behavior of the elaborated nanocomposite (Sep-G@DGE) was studied at different pH values and showed distinct pH-dependent release profiles. The rates were in the following order: acidic > alkaline > neutral. Electrochemical properties of Sep-G@DGE were investigated on a bare mild steel electrode in 0.1 M NaCl solution, demonstrating a corrosion inhibition efficiency of 90 % for a 24-hour immersion time at a concentration of 1 g/L. Moreover, the beforehand prepared nanocontainer, Sep-G@DGE, was incorporated into an alkyd resin to formulate a smart anti-corrosion coating. This coating exhibited enhanced anti-corrosion properties and sustained inhibitory effects over time compared to that of a pure alkyd coating. The coating's efficiency is attributable to the high dispersion of the layered clay mineral structure, which allowed an on-demand release of the DGE inhibitor. In addition, the presence of free APDEMS NH3+ group leads to the formation of electrostatic interactions with the adsorbed chloride ions on the metal surface, acting thus as a barrier against corrosive agents and inhibit rust formation in paint cracks.

Highly efficient corrosion inhibitor for low charge voltage and long lifespan rechargeable aqueous zinc-air battery

Hydrogen evolution, passivation and dendrite growth problems faced by zinc anodes of aqueous zinc-air batteries greatly reduce their cycle life and hinder their application in energy storage devices. Herein, a reversible, corrosion-resistant, and long-term stable cycle-life zinc anode is achieved by introducing zinc acetate and zinc gluconate into an alkaline electrolyte as corrosion inhibitors. Zinc acetate adsorbed on the surface of the zinc anode could be able to regulate the anode/electrolyte interface and thus inhibit the growth of dendrites, and zinc gluconate can reduce the charge voltage on the cathode to regulate the oxidation reaction and then prolong the cycle life, which eventually inhibit zinc anode corrosion. The additive package of zinc acetate and zinc gluconate provides a better performance. With addition of corrosion inhibitors, Zn||Cu cells show a high average coulombic efficiency about 94 %, and zinc-air batteries achieve a cycling lifespan of 297 h and low charge voltage of 1.7 V. This work provides a simple but practical guideline for high-performance zinc-air batteries.

Zea mays bracts extract as an eco-friendly corrosion inhibitor for steel in HCl pickling solution: Experimental and simulation studies

Active phytochemicals with unique electron structures can adsorb on metal surfaces and effectively mitigate metal corrosion. Recently, plant extracts have garnered significant attention as green and renewable corrosion inhibitors. In this study, the abundant agricultural byproducts, namely Zea mays bracts, were used as the extract raw materials, and Zea mays bracts extract (ZMBE) was served as an eco-friendly corrosion inhibitor for mild steel (MS) in 1 M HCl pickling solution. The organic substances in ZMBE were analyzed via ultra-high performance liquid chromatography- quadrupole time-of-flight mass spectrometry (UPLC-QTFMS). The interaction between the active functional groups and MS was investigated using Fourier transform infrared (FT-IR) and ultraviolet–visible (UV–visible) spectroscopy and X-ray photoelectron spectroscopy (XPS). The corrosion inhibition behavior was scrutinized through potentiodynamic polarization (PDP) curves and electrochemical impedance spectroscopy (EIS). The results show that functional groups such as aromatic rings, double bonds, and hydroxyls successfully adsorb on the MS surface to form the protective films. ZMBE exhibits a mixed-type corrosion inhibition with a “geometric coverage” effect. The corrosion inhibition efficiency (η) increases with ZMBE concentration and solution temperature, the optimum η with 5.0 g·L−1 ZMBE at 318 K is 96.2 %. The adsorption of active ingredients follows the Langmuir and El-Awady isotherms. Density functional theory (DFT) and molecular dynamics (MD) simulations prove the synergistic effect of complex components in ZMBE and the corrosion inhibition mechanism. ZMBE is a promising acid pickling corrosion inhibitor with broad application prospects.

The effects of aging time on the corrosion inhibition performance of KI and its synergistic effect with a typical phosphorus-based ionic liquid inhibitor

Potassium iodide (KI) is regarded as an ideal synergist for typical corrosion inhibitors. However, the synergistic effect of KI may be compromised due to its oxidation in acidic solutions. In this work, the anticorrosion performance of KI with different aging times in HCl solution and their synergistic effect with dodecyltriphenylphosphonium bromide (C12TPB) were evaluated via electrochemical tests and surface characterization techniques. The corrosion inhibition efficiency of KI gradually increased from 6.41 % to 38.99 % with increasing aging time to 6 h, while the synergy coefficient between KI and C12TPB abnormally decreased from greater than 1.0 to less than 0.4. UV–vis results and quantum chemical calculation demonstrated that the generated I3− during the aging process caused negative impact on the adsorption of C12TPB, leading to the reduced anticorrosion performance. This study provides valuable insights for the rational utilization of KI as the corrosion inhibitor and synergist.

Experimental, theoretical and computational studies of oxalyl dihydrazide as a novel corrosion inhibitor for mild steel in neutral saline solution

In this work, the corrosion inhibition performance and mechanism of oxalyl dihydrazide (ODH) for mild steel in neutral saline solution are in-depth studied using weight-loss and electrochemical tests, surface characterizations, theoretical calculation and computational simulations. Results indicate that ODH can act as a novel and superior mixed-type corrosion inhibitor for mild steel in neutral saline solution, its corrosion inhibition efficiency increases with the rising ODH concentration, and the optimum value reaches 88.7 % with adding 200 mg/L. Its corrosion inhibition ability becomes better with immersion time. A compact corrosion product film mainly consisting of Fe, O, N and Cl elements formed on metal surface after adding ODH. ODH molecules adsorb on metal surface in an orderly fashion to form a hydrophobic film, which is belonging to the physicochemical adsorption and obeys the Langmuir adsorption isotherm model. The corrosion inhibition process of ODH molecule on mild steel is the endothermic process, which enlarges the activation energy barrier of corrosion reactions. ODH molecule can expel the adsorbed water molecules on metal surface and form copolymers with increasing of ODH concentration, retarding the diffusion of water molecule thus protecting metal from corrosion. ODH is proved to be an effective organic corrosion inhibitor for protecting mild steel in neutral saline solution, and contributes toward research and application of easily accessible sources for organic corrosion inhibitors.

Excellent inhibition performance of an imidazole based ionic liquid on steel-N80 in 15 % hydrochloric acid medium

Imidazoline phenyl thiourea iodized n-butane quaternary ammonium salt (IMSQ) is synthesized from oleic acid, diethylenetriamine, iodinated n-butane, and n-phenylthiourea. The corrosion inhibition performance is studied by electrochemical test. The experimental findings underscored a pronounced positive correlation between the concentration of IMSQ and its corrosion inhibition efficacy on N80 steel. Notably, at a concentration of 0.07 mM, IMSQ attained a corrosion inhibition efficiency of 99.1 %, exhibiting exceptional protective capability for N80 steel in hydrochloric acid environments. By studying the adsorption isotherm equation, it is judged that the type of adsorption includes physical adsorption and chemical adsorption. The characterization analysis results indicate that IMSQ can adsorb on the surface of steel-N80, providing effective protection for the metal.

Facile synthesis, corrosion inhibition, adsorption and DFT studies of 2-(4-(methylsulfanyl) phenyl) −4, 5-diphenyl-1H-imidazole for mild steel in acidic environment

A green, solvent-free, cost effective one-pot synthesis method is employed to produce the innovative corrosion-inhibiting compound 2-(4-(methylsulfanyl)phenyl)-4,5-diphenyl-1H-imidazole (MDPI). The molecular structure of MDPI can be identified using CHN analyses, FT-IR, 1H and 13C NMR spectra. Various electrochemical and gravimetric techniques are utilized to evaluate the anti-corrosion properties of MDPI. The results indicate that MDPI effectively inhibits the corrosion of mild steel under all tested conditions. At 306 K, MDPI achieved a maximum corrosion inhibition efficiency of 98.01 % at a concentration of 10 mM. MDPI exhibited strong adsorption and excellent anti-corrosion properties, forming a protective layer on the mild steel surface. The Langmuir adsorption isotherm, with a ΔGoads value of −39.55 kJ/M was found to be more suitable for this study, indicating that the process occurred by physisorption. Tafel curves indicated that MDPI functions as a mixed-type corrosion inhibitor. Surface characteristics were analyzed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and atomic force microscopy (AFM). Quantum chemistry studies revealed a HOMO-LUMO energy gap of 3.926 eV, corroborating the anti-corrosion effectiveness of MDPI in hydrochloric acid solution. MDPI exhibited promising anti-corrosion activity due to its heterocyclic ring containing nitrogen heteroatoms as well as a methylsulfanyl functional group.

Structural effects, corrosion inhibition mechanisms and timeliness of three tetrazole derivatives on copper in a 3.5wt.% NaCl solution

The structural effects, corrosion inhibition mechanisms and timeliness of 5-methyltetrazole (MT), 5-aminotetrazole (AT) and 5-mercapto-1-methyltetrazole (MMT) on copper in a 3.5 wt.% NaCl solution were studied by electrochemical experiments, surface characterizations and theoretical calculations. At the initial soaking stage, MT exhibited higher corrosion inhibition efficiency (99.65 %), which might stem from the electron donating effect and hydrophobic interaction of -CH3. While MMT exhibited lower corrosion inhibition efficiency (92.64 %), which might stem from the electron withdrawing effect and hydrophilicity of -SH. As the soaking time prolonged, the corrosion inhibition efficiencies of AT and MMT increased (99.49 % and 99.51 %). This might be because the N and S atoms of -NH2 and -SH could also provide lone pair electrons to coordinate with copper, especially S atom. As the soaking time was further prolonged, the formation of corrosion products weakened the interaction between N and S with copper, reducing the corrosion inhibition performance of AT and MMT. MT, AT and MMT molecules on Cu (111) surface can mainly undergo perpendicular adsorption, simultaneously accompanied by parallel adsorption.

Electrodeposition of myristate based superhydrophobic coatings on steel with enhanced corrosion resistance and self-cleaning property

In recent decades, superhydrophobic (SHP) coatings have gained significant attention because of their versatile applications. Superhydrophobic coating is considered as a promising solution to combat corrosion and biofouling issues encountered by steel components in various industries. Using a one-step electrodeposition technique, a superhydrophobic coating with strong corrosion resistance and anti-biofouling property was fabricated on carbon steel in this work. With a water contact angle (WCA) of 170.3 ± 4.2° and a sliding angle (SA) of ∼1°, the wettability of the surface was optimized by varying the electrodeposition potential and deposition time. The as-developed superhydrophobic carbon steel surfaces were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), laser Raman spectroscopy (LRS), Energy dispersive X-ray (EDS) spectroscopy and X-ray diffraction (XRD). Employing field emission scanning electron microscopy (FESEM), the morphology of the superhydrophobic coatings was examined. Potentiodynamic polarization (PDP) technique was used to study the anti-corrosion property of SHP coating and bare sample in 3.5 wt% NaCl solution. The superhydrophobic coating was found to exhibit 99 % corrosion inhibition efficiency. In addition, the biofouling resistance of the coating was evaluated in both gram-negative and gram-positive bacterial cultures and compared with the uncoated sample. Total viability count (TVC) for the SHP coated samples was 5 orders less as compared to the uncoated sample exposed to gram-negative bacterial culture. Similarly, 4 orders reduction in TVC was estimated for the SHP coated sample as compared to the uncoated sample in gram-positive bacterial culture. The impact of superhydrophobic coating on the corrosion performance and biofouling properties of carbon steel was investigated along with the self-cleaning property and robustness of the coating.

Step-by-step design of new phenyl-1,2,3-triazole derivatives with improved anti-corrosive properties: A combined DFT and MD simulation study

In this study, 35 new inhibitors were designed theoretically through the step-by-step strategy based on a new organic non-planar inhibitor 1-benzyl-4-phenyl-1H-1,2,3-triazole (BPT). The first step is to replace one parent phenyl group by six other groups (–Cl, –Br, –OH, –NH2, –OCH3, –thiazole) with heteroatoms, trying to add the adsorption sites and reduce the energy gap. The second step is to use two bridge groups (–S–, –NH–) to displace the original bridge group (–CH2), or to delete the bridge group directly, tending to further add the adsorption sites, reduce the energy gap and change BPT to planar molecules. The final step is to use the combination of oxa and carbonylation substitution strategy on the six compounds with lowest energy gap obtained from the previous two step modifications, in order to further add the adsorption sites, reduce the energy gap and change BPT to planar molecules. Based on the quantum chemical calculations, it is found that main key parameters to anti-corrosive properties like the softness, electron affinity and energy gap were improved greatly compared to BPT. Three new planar molecules (E5, E6 and E6) which have high chemical reactivity, high binding energy with metals, and low energy gap were found successfully, which may be attractive potential inhibitors used as the corrosion inhibition to Fe-related alloy. The corrosion inhibition mechanism of E5 to E7 is different to that of BPT, in which the whole structure will make contributions to the interaction with metals to increase the binding energy and the corrosion inhibition efficiency. This work may provide a unique view for the design and development of new advanced inhibitor.

Dual pH and NIR-controlled release system for metal coating protection

Mesoporous materials are often utilized as nanocarriers to encapsulate corrosion inhibitors. However, the loading process is often complex, and the loading efficiency of corrosion inhibitors is unsatisfactory. In this research, we present a strategy for one-pot encapsulation of benzotriazole (BTA) in polypyrrole (PPy). The prepared composite material (PPy@BTA) can release corrosion inhibitors in response to acid and alkali stimulation and has the ability of near-infrared (NIR) photothermal response. Electrochemical impedance spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, and wire beam electrode techniques were employed to confirm the self-healing property of the scratched coating embedded with PPy@BTA. Results indicated that the combination of NIR and pH-responsive self-healing effects endowed the composite coating with a long-term protection effect and repeatable self-healing behavior. This research broadens the scope of the use of PPy and provides new strategies for metal corrosion protection.

Evaluation of green corrosion inhibitors of chitosan oligosaccharide derivatives for CO2 corrosion inhibition on 20# carbon steel

Two chitosan oligosaccharide derivatives, VCOS and GCOS, were synthesized and explored as corrosion inhibitors, the synergistic inhibition effect of KI and VCOS was also studied. Their structures were elucidated using Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance. The inhibition efficacy of VCOS+KI and GCOS on 20# steel within an 80℃, 3 wt% NaCl, CO2-saturated solution system was investigated employing various techniques, including gravimetric measurement, electrochemical analysis, Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and molecular dynamics simulations. The results reveal that the inhibition efficiency of VCOS is relatively low when it acts alone. When VCOS and KI are combined, they have a good synergistic effect, and the synergistic parameter is the highest at 6.209. In the weight loss experiment, the corrosion inhibition efficiency increased with the concentration of the corrosion inhibitor. The inhibition rates of VCOS+KI and GCOS were 90.5 % and 90.2 %, respectively. The adsorption on 20# steel conformed to the Langmuir isotherm adsorption equation. The measurement results of SEM, Energy Dispersive Spectroscopy, and AFM show that VCOS+KI and GCOS adsorbed on the surface of carbon steel to form a dense inhibitor film, which effectively protected the metal substrate. According to the polarization test results, both VCOS+KI and GCOS are mixed-type inhibitors primarily exhibiting anodic inhibition, with inhibition efficiencies reaching 98.9 % and 95.1 %, respectively. Electrochemical impedance spectroscopy tests showed that with increasing inhibitor concentration and immersion time, Rct increased and Cdl decreased, resulting in a gradual increase in inhibition efficiency and the formation of a dense and stable inhibitor film. The results indicate that VCOS+KI and GCOS are non-toxic, water-soluble, and environmentally friendly inhibitors with good anti-corrosion performance.

Carbazole derivatives as antioxidant and anticorrosion materials

In this study, a series of new carbazole derivatives were studied using several reactions, including the Vilsmeier–Haack reaction. A cyclization reaction within bromoacetic acid was reported to synthesize thiazolidinone compounds, followed by the Mannich reaction by reacting the prepared compound with formaldehyde and secondary amines, that is, diphenylamine, morpholine, and phthalimide. All synthesized compounds were characterized by infrared spectroscopy, liquid chromatography–mass spectrometry, and 1H and 13C nuclear magnetic resonance spectroscopy. The antioxidant activities of all prepared compounds were studied using the free-radical scavenging method using 2,2-diphenyl-1-picrylhydrazyl, demonstrating their moderate activity compared with ascorbic acid as the standard substance. The effectiveness of the prepared compounds as corrosion inhibitors was studied in an acidic medium of sulfuric acid (0.25 mol/L) using the electrochemical method. Acceptable corrosion-inhibition efficiency was achieved, with the highest inhibition rate of 55.21 % for compound VII.

Experimental, electrochemical and DFT simulation studies of a novel Schiff base derivative as an efficient mild steel corrosion inhibitor in acidic environments

A newly synthesized Schiff base, consisting 3-methyl-2-{(E)-[(2E)-3-phenylprop-2-en-1-ylidene] amino} butanoic acid, is utilized to prevent mild steel from corroding in acidic environments. FTIR spectra validate the prepared SB. The corrosion rate at various temperatures was measured using electrochemical techniques like as polarization and electrochemical impedance tests. At a higher temperature of 333K, this molecule exhibits about 90% inhibition efficacy with 50 ppm inhibitor. The corrosion inhibition mechanism was measured using thermodynamic and adsorption characteristics. These findings suggest that chemical adsorption causes a surface layer to form on the metal surface. The Langmuir adsorption isotherm is followed. The creation of the adsorption layer on the metal surface is confirmed by SEM and AFM pictures. Quantum chemical calculations were calculated and discussed.

Investigating the synergistic effect of iodide ion and Michelia alba leaf extract on carbon steel in 0.5 M H2SO4

The study examined the inhibitory effect of Michelia alba leaf extract (MALE) on carbon steel (CS) in 0.5 M H2SO4 solution. Furthermore, the investigation explored the effect of KI to enhance the protection provided by MALE. The study demonstrates that both MALE and KI have corrosion inhibiting properties on CS in acidic solutions. However, when MALE and KI are combined, they exhibit a greater inhibitory effect. Corrosion inhibition efficiency was limited to 86.55 % with 400 mg/L MALE. The maximum corrosion inhibition efficiency was 51.84 % when 400 mg/L KI was used alone. However, when 800 mg/L MALE was combined with 400 mg/L KI in 0.5 M H2SO4 solution, the efficiency increased to 95.02 %. This increase can be attributed to the synergistic effect between MALE and KI. The SEM and XPS results further confirmed that the addition of KI could be more effective in preventing the corrosion of CS. The theoretical calculations demonstrate that constituents found in the extract, which are rich in hydroxyl groups, benzene rings, N and S atoms have a higher probability of adsorption onto the CS surface in parallel, thereby increasing the efficiency of corrosion inhibition significantly.

Developing a novel imine derivative as a corrosion inhibitor for Q235 carbon steel in 1 M HCl solution: Experiments and theoretical calculations

During oil and gas extraction, metals are inevitably exposed to acidic environments on a regular basis. Acid solutions, particularly hydrochloric acid, are employed in a multitude of industrial processes, including oil well acidising, steel pickling, ferroalloy pickling and acid cleaning. These applications frequently result in severe metal corrosion. To cope with corrosion, the superlative simple and effective method is to prevent corrosion inhibitors. Naphthyridinimides are not as effective as rust inhibitors, but their corrosion inhibition is significantly improved by the addition of Br ions. This thesis focuses on the synthesis of naphthylimine-type novel organic corrosion inhibitors and the corrosion inhibition mechanism, with the main content of 3,3′-(1,3,6,8-tetraoxo-1,3 6,8-tetrahydrobenzo[lmn] [3,8] phenanthroline-2,7-diyl) bis (N-ethyl -N, N-Dimethyl-1-propylamine) bromide (NDI-N-Br) on Q235 carbon steel in an acidic environment (1 M hydrochloric acid solution). The corrosion inhibition efficiencies of NDI-N-Br reached 93.53 % at 300 ppm at an ambient temperature of 298 K. The corrosion inhibitor NDI-N-Br forms a protective film on the metal surface and organizes the interaction between the metal matrix and the corrosive medium, providing a rust inhibiting effect. This thesis shows that this class of compounds can be well applied to acidic environments and provide ideas for the subsequent development of naphthylimide-based organic corrosion inhibitors.

Imidazolium-Based Polymeric Ionic Liquids with Short Alkyl Chains as Green Corrosion Inhibitors for Mild Steel in 1 M HCl: Experimental and Theoretical Investigations.

A novel polymeric ionic liquid (PDBA-IL-NH2) using imidazolium ionic liquids with short alkyl chains as monomers and two control ionic liquids (PDBA-IL-OH and PIL-NH2) were synthesized. Their inhibition properties and mechanisms were explored via surface analysis, weight loss tests, electrochemical studies, and adsorption isotherm analysis. The corrosion inhibition efficiency (CIE) of PDBA-IL-NH2 gradually increased with increasing concentration, and the largest efficiency was 94.67% at 100 ppm. At the same concentration (50 ppm), the corrosion inhibition abilities of inhibitors were in the order of PDBA-IL-NH2 > PDBA-IL-OH > PIL-NH2 > IL-NH2. Based on the experimental investigation, the synergistic effect of electrostatic interaction, protonation, and electron donor-acceptor interaction facilitated the intensive entanglement and coverage of PDBA-IL-NH2 with the reticulated form on the metal, and the generated densest films protected the metal from the corrosive media. Ultimately, the theoretical results of molecular dynamics simulations and quantum chemical study were in high agreement with the experimental data, which confirmed the proposed inhibition mechanisms on the microscopic scale. This study contributed valuable perspectives to the design of efficient and ecofriendly corrosion inhibitors.

Comprehensive investigation of a new pyrazole derivative Schiff base complex: Revealing its potent protection against carbon steel corrosion

A new pyrazole derivative from 4-Aminoantipyrine Schiff base complex, which has the potential for corrosion inhibition, have been successfully synthesized (HL). The objective of this research is to enhance the corrosion inhibition activities of the synthesized HL by coordinating it with Cobalt to form complex compound (Co-L) on mild steel. HL and Co-L molecules will be immobilized on the surface of mild steel, creating a protective layer against corrosion-causing species. The synthesized compounds underwent characterization using various techniques, including UV-Visible Spectrophotometer, Fourier Transform Infrared, Nuclear Magnetic Resonance, X-Ray Diffraction, Magnetic Susceptibility Balance, and Elemental Analysis, confirming the success of the synthesis. Corrosion tests were conducted using the Weight Loss method and Potentiodynamic Polarization (PDP). The results indicate that the complex forms of compounds exhibit higher corrosion inhibition efficiency compared to their ligands. In the Weight-Loss method test (in 1.0 M HCl solution), Co-L compounds demonstrated superior performance efficiency at a concentration of 1 ×10−4 M, reaching 92.96 %, while HL showed an efficiency of only 86.89 %. The PDP test revealed that the HL and Co-L exhibited inhibition efficiencies of 87.13 % and 93.97 %, respectively, at a specific concentration. Monte Carlo simulation further supported these findings, indicating that inhibitor molecules are adsorbed on the metal surface, with the energy of adsorption for the Co-L inhibitor surpassing that of HL. This simulation result correlates linearly with experimental observations.