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Membrane technology is rapidly gaining broad attraction as a viable alternative for carbon capture to mitigate increasingly severe global warming. Emerging CO2‐philic membranes have become crucial players in efficiently separating CO2 from light gases, leveraging their exceptional solubility‐selectivity characteristics. However, economic and widespread deployment is greatly dependent on the boosted performance of advanced membrane materials for carbon capture. Here, we design a unique gel membrane composed of CO2‐philic molecules for accelerating CO2 transportation over other gases for ultrapermeable carbon capture. The molecular design of such soft membranes amalgamates the advantageous traits of augmented permeation akin to liquid membranes and operational stability akin to solid membranes, effectively altering the membrane's free volume characteristics validated by both experiments and molecular dynamics simulation. Surprisingly, gas diffusion through the free‐volume‐tuned gel membrane undergoes a 9‐fold improvement without compromising the separation factor for the superior solubility selectivity of CO2‐philic materials, and CO2 permeability achieves a groundbreaking record of 5608 Barrer surpassing the capabilities of nonfacilitated CO2 separation materials and exceeding the upper bound line established in 2019 even by leading‐edge porous polymer materials. Our designed gel membrane can maintain exceptional separation performance during prolonged operation, enabling the unparalleled potential of solubility‐selective next‐generation materials towards sustainable carbon capture. [ABSTRACT FROM AUTHOR]

Membrane technology is rapidly gaining broad attraction as a viable alternative for carbon capture to mitigate increasingly severe global warming. Emerging CO2‐philic membranes have become crucial players in efficiently separating CO2 from light gases, leveraging their exceptional solubility‐selectivity characteristics. However, economic and widespread deployment is greatly dependent on the boosted performance of advanced membrane materials for carbon capture. Here, we design a unique gel membrane composed of CO2‐philic molecules for accelerating CO2 transportation over other gases for ultrapermeable carbon capture. The molecular design of such soft membranes amalgamates the advantageous traits of augmented permeation akin to liquid membranes and operational stability akin to solid membranes, effectively altering the membrane's free volume characteristics validated by both experiments and molecular dynamics simulation. Surprisingly, gas diffusion through the free‐volume‐tuned gel membrane undergoes a 9‐fold improvement without compromising the separation factor for the superior solubility selectivity of CO2‐philic materials, and CO2 permeability achieves a groundbreaking record of 5608 Barrer surpassing the capabilities of nonfacilitated CO2 separation materials and exceeding the upper bound line established in 2019 even by leading‐edge porous polymer materials. Our designed gel membrane can maintain exceptional separation performance during prolonged operation, enabling the unparalleled potential of solubility‐selective next‐generation materials towards sustainable carbon capture. [ABSTRACT FROM AUTHOR]

Abstract A new pyrazolotriazole derivative, namely, 1-acetyl-6-methyl-1H-pyrazolo [3,2-c][1,2,4]triazole (APT) was synthesized. The corrosion inhibition performance of APT on carbon steel in 1 M hydrochloric acid solution was investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) methods. The results showed that the inhibition efficiency of APT increases with concentration and attains its maximum of 93% at 10−3 M. The potentiodynamic polarization study suggests that APT acts as mixed type inhibitor. The EIS studies show that APT produces a covering layer at the metal/electrolyte interface. The adsorption of this compound on steel surfaces followed a Langmuir adsorption isotherm. DFT calculations at the B3LYP level of theory and the analyses of frontier orbitals allow the determination of the active adsorbed sites of APT on the metal surface, and molecular dynamics simulations further illustrate the most reasonable adsorption configuration. Graphical abstract Image 1 Highlights • Synthesis of a new 1-acetyl-6-methyl-1H-pyrazolo [3,2-c][1,2,4]triazole derivative (APT). • 3D structure is elucidate using XRD and confirmed by DFT calculations. • APT corrosion inhibition on carbon steel in 1 M HCl solution is investigated. • The inhibition efficiency of APT increases with concentration. • MD simulations suggest the parallel adsorption model of APT on iron substrate. [ABSTRACT FROM AUTHOR]

Abstract The inhibitive action of three newly synthesized triazolotriazepine derivatives, namely, 9‑ethyl‑6‑methyl‑7H‑1,2,4‑triazolo[4,3‑b][1,2,4‑triazepin‑8(9H)-one (TTY), 7,9‑didecyl‑6‑methyl‑7H‑1,2,4‑triazolo[4,3-b][1,2,4]triazepin‑8‑one (TTY4), and 7,9‑ditetradecyl‑6‑methyl‑7H‑1,2,4‑triazolo[4,3‑b][1,2,4]triazepin‑8‑one (TTY5) for carbon steel in 1 M HCl is investigated using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and surface analysis techniques. The results show that the corrosion of carbon steel in HCl solution is efficiently inhibited by these new organic inhibitors. The adsorption of tested inhibitors on carbon steel surface is found to be spontaneous and obeyed the Langmuir adsorption isotherm. The anti-corrosion mechanism of these new inhibitors on iron was further revealed by quantum chemical calculations and molecular dynamics simulations. In agreement with the experimental data, theoretical results showed that the order of inhibition efficiency is TTY5 > TTY4 > TTY. Graphical abstract Unlabelled Image Highlights • Synthesis and spectroscopic characterization of new triazolotriazepine derivatives • Corrosion inhibition on carbon steel in 1 M HCl is achieved using EIS and PDP methods. • The corrosion inhibition efficiency increases with inhibitor concentration. • MD simulation results are in accordance with the observed inhibition efficiencies. [ABSTRACT FROM AUTHOR]

The mutually corroborated electrochemical measurements and theoretical calculations were used to investigate the corrosion inhibition performances of purpald (4-amino-3-hydrazino-5-mercapto-1,2,4-triazole, AHMT) and its synergistic effect with tartaric acid (TA) on mild steel in 0.5 M H2SO4 solution. The experimental results show that the inhibition efficiency increases with the concentration of AHMT and increases further when TA exists. Density functional theory (DFT) calculations were performed to interpret the measured data and trends observed in the electrochemical studies. Furthermore, molecular dynamic simulation revealed a nearly flat configuration for molecules on metal surface with negative adsorption energies in a sequence agreed with experimental observation. [ABSTRACT FROM AUTHOR]

The mutually corroborated density functional theory (DFT) and molecular dynamics (MD) simulation methodology were employed to evaluate the inhibition performance of three thiourea derivatives (Inh1, Inh2, and Inh3) on carbon steel corrosion. Experimental results have shown that the corrosion rate follows the order: Inh3 > Inh2 > Inh1. Quantum chemical descriptors such as the frontier orbital energies ( E HOMO and E LUMO ), the energy gap between E LUMO and E HOMO (Δ E ), dipole moment (μ), and Fukui index have been calculated and discussed. Some significant factors such as solvent, temperature, and coverage have been considered when investigating the adsorption of aforementioned thiourea derivatives on Fe(1 1 0) surface. Our results provide important atomic/molecular insights into the anticorrosive mechanism of inhibitor molecules, which could help in understanding the organic-metal interface and designing more appropriate organic corrosion inhibitors. [ABSTRACT FROM AUTHOR]

Al-air battery is a kind of chemical battery exhibiting high theoretical energy density. However, the hydrogen evolution corrosion is the primary barrier to its widespread application. Herein, an imidazole-based ionic liquid, i.e., 1-(2-hydroxyethyl)-3-methylimidazolium chloride (HMIC), was examined as a corrosion inhibitor for Al-5052 alloy in 4 M NaOH electrolyte by electrochemical means, hydrogen evolution test and surface characterization. Electrochemical results showed that the inhibition efficiency was 58.2% when the concentration of HMIC was 7 mM, and the anode utilization increased to 82.9%. The findings of X-ray photoelectron spectroscopy (XPS) and molecular dynamics simulation demonstrated that HMIC can adsorb on the surface of Al-5052 to form a protective barrier and prevent the self-corrosion of Al anode. Moreover, the addition of HMIC significantly improved the discharge performance of the Al-air battery, with a nominal specific capacity (2469 mAh g−1) and energy density (3313 Wh kg−1). This electrolyte regulation strategy offers a way to enhance the Al-air battery's performance in alkaline medium. [Display omitted] • An ionic liquid (HMIC) was evaluated as a corrosion inhibitor for Al-air battery. • The addition of HMIC significantly increased the corrosion resistance of Al anode. • Surface characterization of Al-5052 alloy was examined by SEM, AFM, and XPS. • Energy density and anode utilization of the full battery were improved. • The inhibition mechanism of HMIC additive was elaborated. [ABSTRACT FROM AUTHOR]

• Surface morphology analysis provided that psidium guajava linn leaves extract exhibit excellent anti-corrosion ability. • Electrochemical test indicate psidium guajava linn leaves extract belong to the mixed-type inhibitor. • Psidium guajava linn leaves extract adsorb on the Cu surface in accordance with the Langmuir model. This work multi-angle explored the anti-corrosion nature and mechanism of psidium guajava linn leaves extract for copper in H 2 SO 4 environment.In this study, we used a simple and eco-friendly extraction way to acquire psidium guajava linn leaves extract (PGLLE). Fourier Transform infrared spectroscopy (FTIR) was executed to determine the active functional groups in PGLLE. Quantum chemical calculations effectively forecast the anti-corrosion characteristic of the four active substances in PGLLE. The results of molecular dynamics simulation predicted the stabilized adsorption configurations of the four substances in PGLLE on the Cu (1 1 1). Surface topography analysis can intuitively demonstrate that PGLLE effectually inhibits Cu corrosion. The data of electrochemical experiments show that the anti-corrosion capacity of PGLLE increases with the increase of the concentration in a certain interval. As the temperature hoists at definite temperature range, PGLLE can still be efficaciously adsorbed at the Cu surface, showing high-quality corrosion inhibition capabilities. Psidium guajava linn leaves can exist widely in nature, so it has great economic value as the inhibitor. Besides, PGLLE basically does not pollute the ecosystem when used as inhibitors. [ABSTRACT FROM AUTHOR]

In this work, we used experimental and theoretical calculation methods to investigate the corrosion inhibition nature of banana leaves water extract (BLWE) for X70 steel at 1 mol/L hydrochloric acid environment. The data of electrochemical tests manifest that the hydrochloric acid medium will accelerate the corrosion of X70 steel with increasing temperature. The charge transfer resistance dropped sharply from 55 Ω cm2 at 298 K to 18.4 Ω cm2 at 313 K. After adding BLWE in hydrochloric acid solution, the anti-corrosion efficiency of banana leaves extract for X70 steel can be maintained at about 90%. BLWE can simultaneously inhibit the anodic and cathodic reactions of X70 steel in hydrochloric acid solution, so it is mixed-type inhibitor. Surface morphology analysis strongly shows that BLWE can effectually restrain the corrosion of X70 steel. BLWE adsorption at the X70 steel surface is accord with Langmuir single-deck adsorption. Quantum chemical (QC) calculation and molecular dynamics simulations (MDS) have shown that (S)-2-amino-3-(4-hydroxyphenyl)propanoic acid (AHP), 3-(2-aminoethyl)-1H-indol-5-ol (ATI), and 3,4-Dihydroxycinnamic Acid (DDA) in BLWE can show excellent anti-corrosion character. QC calculation results show that AHP, ATI and DDA have small dipole moment values. The small dipole moment value is favorable the accumulation of inhibitor molecule on the X70 steel surface, thereby forming a denser barrier film. MDS results show that AHP, ATI and DDA can be adsorbed on the Fe (110) surface in parallel to obtain the maximum coverage. Unlabelled Image • Electrochemical test data indicate BLWE belong to the mixed-type corrosion inhibitor. • Surface characteristics analysis provided that BLWE exhibit excellent corrosion inhibition nature. • BLWE adsorb on the Fe/solution surface in accordance with the Langmuir model. [ABSTRACT FROM AUTHOR]

In order to reduce the investment of corrosion inhibitors, based on experimental and theoretical studies, the corrosion inhibition and mechanism of new imidazoline derivatives (SMIS) and 2‐aminopyridine (AMP) were investigated carefully. The best corrosion inhibition effect was at 0.7‐g/L SMIS and 0.3‐g/L AMP, the corrosion inhibition efficiency of weight loss, electrochemical impedance spectroscopy, and potentiodynamic polarization (Tafel) were 90.54%, 98.56% and 97.68%, respectively. Electrochemical research shows that SMIS&AMP belongs to cathodic corrosion inhibition. SMIS&AMP mainly increased the film resistance and charge transfer resistance in 1‐M HCl, thus playing a certain role in corrosion inhibition. X‐ray photoelectron spectroscopy and energy dispersive spectrometer proved that SMIS&AMP can be adsorbed on the surface of Q235, molecular dynamics showed that there was a certain synergy between SMIS and AMP. This study confirmed that SMIS and AMP have a good synergistic effect, improve the corrosion inhibition efficiency, reduce the synthesis cost of SMIS, and have a certain guiding significance for synergistic corrosion inhibition. [ABSTRACT FROM AUTHOR]

An amino acid ionic liquid, namely 1-octyl-3-methylimidazolium L-prolinate ([OMIM]L-pro), was investigated as the corrosion inhibitor of copper in 3.5% NaCl solution through electrochemical techniques, surface analysis and molecular dynamics simulation. The results showed that [OMIM]L-pro was a mixed type inhibitor with a predominantly anodic action for copper in NaCl solution, its inhibition efficiency increased with the increase of concentration, but decreased with rising temperature, the highest inhibition efficiency was up to 97.5%. The adsorption of [OMIM]L-pro on the copper surface was found to follow the Langmuir isothermal equation, and the corrosion kinetic characteristics of copper in the test solution was discussed and analyzed. Moreover, L-prolinate anion was found to play a significant role in the corrosion inhibition performance of [OMIM]L-pro, but there was a synergistic effect between L-prolinate anion and imidazolium cation, which synergistically inhibited the corrosion of copper in NaCl solution. Molecular dynamics simulation data supported the experimental results. [ABSTRACT FROM AUTHOR]

Quantum chemical approaches are very much significant in the field of corrosion chemistry to understand the structure-property relationship of various organic molecules as corrosion inhibitors. Here is the adsorption behavior of three organic azo-dyes, viz. 6-((4-(diethylamino)-2-methylphenyl)diazenyl)benzo[de]isochromene-1,3-dione (named as Dye-1); 4-[6-[2-[4-(N,N-Diethylamino)-2-methylphenyl]diazenyl]-1,3-dioxo-1H-benz[de]isoquinolin-2(3H)-yl]-N-(2-thiazolyl)benzenesulfonamide (named as Dye-2); 4-[6-[2-[4-(N,N-Diethylamino)-2-methylphenyl]diazenyl]1,3-dioxo-1H-benz[de]isoquinolin-2(3H)-yl]-N-(2-pyrimidinyl)benzenesulfonamide (named as Dye-3) on the rutile TiO2 and ZnO surfaces have been explored via quantum chemical approach, i.e. density functional theory (DFT), local reactive sites analysis and molecular dynamic (MD) simulation studies. Global relativities of the dye molecules have been explored by calculating the energy of the frontier molecular orbitals, energy difference (ΔΕ), electronegativity (χ), electron affinity (A), softness (σ), and hardness (η) like quantum chemical parameters. Furthermore, MD simulation study has been performed to comprehend the adsorption behaviour as well as the adsorption configuration of three selective dye molecules on TiO2 and ZnO surfaces mimicking the real adsorption and surface protection phenomenon. The mechanisms of adsorption behaviour of three organic azo dyes on the TiO2 and ZnO surfaces have been explored at the atomistic level. Fukui indices analysis revealed the presence of locally reactive sites responsible for adsorption. MD simulation results revealed the adsorption of dye molecules onto the metal oxide surfaces occurs in a horizontal fashion. The horizontal adsorption of dye molecules undergoes both physisorption and chemisorption on the metal oxide surface leading to greater surface coverage. [ABSTRACT FROM AUTHOR]

In the present work, essential oil of Calamintha (EOC) was extracted from Calamintha plant and characterized by gas chromatography-mass spectrometry (GC-MS) and FTIR technique. In addition, EOC was evaluated as an ecological corrosion inhibitor of mild steel in 1 M HCl medium by various electrochemical techniques. Satisfactory consistency was obtained between the gravimetric method, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The maximum efficiency was recorded for the concentration of 1.5 g/L EOC which reached 87.57%. However, the morphology of the metal surface analyzed by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) showed the appearance of a protective barrier on the steel surface. Finally, a theoretical study was carried out on the basis of the density functional theory (DFT) and molecular dynamics (MD) simulation technique. [ABSTRACT FROM AUTHOR]

Omeprazole (OL) as a green and efficient drug corrosion inhibitor was first investigated for the corrosion inhibition of Q235 carbon steel at 298, 308, and 318 K. Open circuit potential, Tafel, electrochemical impedance spectroscopy, and weight loss were used to evaluate the inhibition performance toward Q235 carbon steel in HCl medium. The results showed that OL exhibited excellent corrosion protection to carbon steel at different temperatures because of forming the compact and ordered OL adsorption film on Q235 surface. Especially, the inhibition efficiency increased to 96.11%, 95.12%, and 94.04% for 40‐mg/L OL in Tafel at 298, 308, and 318 K. Meanwhile, N–Fe and S–Fe bonds determined from X‐ray photoelectron spectroscopy revealed the multiple anchoring interactions between steel and OL with S and N atoms as the active sites. Density functional theory and molecular dynamics simulations showed the low energy gap ΔE and high adsorption energy values, besides the radial distribution function (RDF) indicating the strong chemical sorption of OL on Fe surface, which proved the superior corrosion inhibition efficiency of OL at a molecular or atomic level. [ABSTRACT FROM AUTHOR]

The adsorption behavior and inhibition mechanism of five synthesized bis-azo dye (BAD) derivatives on the corrosion of iron in aerated HNO 3 and NaOH were investigated by performing potentiostatic polarization, weight loss (WL), thermometric and UV–visible spectra measurements. DFT calculations is applied to study the correlation between corrosion inhibition and global reactivity descriptors such as: E HOMO , E LUMO , molecular gap (Δ E ), the dipole moment ( μ ), the global hardness ( η ), softness( S ), electronegativity ( χ ), proton affinity ( PA ), electrophilicity ( ω ), nucleophilicity ( ɛ ), electrons transferred from inhibitors to metal surface (Δ N ), initial molecule-metal interaction energy (Δ ψ ), total electronic energy ( E ) and the energy change during electronic back-donation process (Δ E b-d ). To mimic the real environment of corrosion inhibition, molecular dynamic (MD) simulations in aqueous phase have also been modelled consisting of all concerned species (inhibitor molecule, H 2 O, H 3 O + ion, NO 3 − ion, OH − and Fe surface). The results confirmed that BAD molecules inhibit iron by adsorption behavior through donating and accepting electrons together with the formation of [Fe (II) and Fe (III)—BAD] chelate complex compounds. BAD's behavior is mainly chemisorption with some physisorption obeyed Frumkin and that of El-Awady adsorption isotherm. Kinetic parameters such as: ( K b , 1/y , K ads , f , Δ G ° ads ) have been determined and discussed. Binding energies of BAD molecules on Fe (110) surface followed the order: BAD _ 2 >  BAD _ 1 >  BAD _ 3 >  BAD _ 4 >  BAD _ 5 . Theoretical results were found to be consistent with the experimental data reported. Our results provide important atomic/molecular insights into the anticorrosive mechanism of inhibitor molecules, which could help in understanding the organic-metal interface and designing more appropriate organic corrosion inhibitors. [ABSTRACT FROM AUTHOR]

Nerve agents pose significant threats to civilian and military populations. The reactivation of acetylcholinesterase (AChE) is critical in treating acute poisoning, but there is still lacking broad-spectrum reactivators, which presents a big challenge. Therefore, insights gained from the reactivation kinetic analysis and molecular docking are essential for understanding the behavior of reactivators towards intoxicated AChE. In this research, we present a systematic determination of the reactivation kinetics of three V agents-inhibited four human ChEs [(AChE and butyrylcholinesterase (BChE)) from either native or recombinant resources, namely, red blood cell (RBC) AChE, rhAChE, hBChE, rhBChE) reactivated by five standard oximes. We unveiled the effect of native and recombinant ChEs on the reactivation kinetics of V agents ex vitro , where the reactivation kinetics characteristic of Vs-inhibited BChE was reported for the first time. In terms of the inhibition type, all of the five oxime reactivators exhibited noncompetitive inhibition. The inhibition potency of these reactivators would not lead to the difference in the reactivation kinetics between native and recombinant ChE. Despite the significant differences between the native and recombinant ChEs observed in the inhibition, aging, and spontaneous reactivation kinetics, the reactivation kinetics of V agent-inhibited ChEs by oximes were less differentiated, which were supported by the ligand docking results. We also found differences in the reactivation efficiency between five reactivators and the phosphorylated enzyme, and molecular dynamic simulations can further explain from the perspectives of conformational stability, hydrogen bonding, binding free energies, and amino acid contributions. By Poisson-Boltzmann surface area (MM-PBSA) calculations, the total binding free energy trends aligned well with the experimental k r2 values. • First reactivation kinetic analysis between native and recombinant ChEs inhibited by V agents. • Recombinant ChEs may replace native ChEs in the research of reactivation kinetics. • MD simulations provide a supportive understanding of the reactivation differences among five reactivators. • The total binding free energy trends aligned well with the experimental k r2 values. [ABSTRACT FROM AUTHOR]

• Aesculus Hippocastanum seeds extract was investigated for corrosion inhibition of Cu-Ni in 5 M H 3 PO 4. • The AHS extract has a flat or nearly flat orientation and provides good surface coverage. • Using 100 ppm AHS extract, an efficiency of 96.1 percent was obtained. • On the Cu-Ni surface, AHS extract compounds formed a protective film. • Experimental findings are supported by quantum calculations and molecular dynamic simulation. In this work, Aesculus Hippocastanum Seeds (AHS) extract has been used as a sustainability and environmentally corrosion inhibitor to reduce the risk of copper alloy corrosion during the acid cleaning process in desalination plants. This extract contains mostly Quercetin 3,4-diglucoside, Aesculin, escin Ia, escin Ib, isoescin Ia, isoescin Ib, Leucocyanidin, Fraxin, Procyanidin A2, Quercetin, and Kaempferol, according to HPLC analysis. At 100 ppm, the AHS extract showed a 96.1 percent inhibitory efficacy as a corrosion inhibitor. The findings demonstrate that AHS is an effective mixed–type corrosion inhibitor. The AHS extract solution has a greater activation energy value (i.e. 7.32 kJ mol−1) than the blank system (i.e. 15.65 kJ mol−1), indicating a physical adsorption process. Furthermore, the Langmuir adsorption pattern is applied to describe AHS extract adsorption. The electron dispersion in inhibitor compounds was revealed by quantum calculations, revealing their capacity to accept/donate charges from Cu-Ni atoms in vacuum and in water solvation. The extract molecules adsorbed on the copper alloy surface in a nearly flat orientation to acquire maximal surface coverage and contact, according to a molecular dynamics simulation. [ABSTRACT FROM AUTHOR]

In the present study, to predict corrosion inhibition performances of 2-amino-4-(4-chlorophenyl)-thiazole (Inh1), 2-amino-4-(4-bromophenyl)-thiazole (Inh2), 4-(2-aminothiazole-4-yl)-phenol (Inh3), 5,5 ′ -(ethane-1, 2-diyldisulfanediyl) bis-(1,3,4-thiadiazole-2-amine) (Inh4), 5,5 ′ -(propane-1,3-diyldisulfanediyl) bis-(1,3,4-thiadiazole-2-amine) (Inh5) against corrosion of Fe metal, density functional theory (DFT) calculations and molecular dynamics simulations approach were performed on these mentioned molecules. Firstly, quantum chemical parameters such as the highest occupied molecular orbital energy ( E HOMO ), lowest unoccupied molecular orbital energy ( E LUMO ), the energy gap between E LUMO and E HOMO (Δ E ), chemical hardness, softness, electronegativity, proton affinity, global electrophilicity, global nucleophilicity and total energy (sum of electronic and zero-point energies) were calculated and discussed with the help of HF/SDD, HF/6-311G, HF/6-31 ++G, B3LYP/SDD, B3LYP/6-311G and B3LYP/6-31 ++G methods. Then, we calculated binding energies on Fe(110) surface of aforementioned thiazole and thiadiazole derivatives to investigate the strength of the interactions between metal surface and these molecules. The theoretical data obtained are in good agreement with the experimental inhibition efficiency results earlier reported. [ABSTRACT FROM AUTHOR]

The corrosion inhibition effect and synergistic mechanism of novel imidazoline derivative (SMIF) and benzimidazole (BMZ) in 3.5 wt% simulated concrete solution were studied experimentally and theoretically. The complex inhibitors have the most outstanding inhibition efficiency when SMIF concentration is 0.1 g/L and BMZ is 0.9 g/L, the corrosion inhibition efficiencies of weight loss, Electrochemical Impedance Spectroscopy and Potentiodynamic polarization curve (Tafel) were 88.81%, 86.27% and 90.22%, respectively. Electrochemistry analysis results proved that the corrosion inhibition mechanism of the inhibitors in the corrosion solution was mainly the formation of a protective film on the surface of carbon steel. FT-IR, Energy Dispersive Spectroscopy and X-ray Photoelectron Spectroscopy all proved the existence of the protective film. Molecular dynamics proved that the composite inhibitor molecules could be stable on the surface of carbon steel and when consist of complex inhibitor was 0.1 g/L SMIF and 0.9 g/L BMZ the stable adsorption morphology were the highest. This work confirmed that SMIF and BMZ inhibitors have a good synergistic effect, greatly improving the inhibition efficiency and reducing the cost of corrosion inhibition, and has a certain guiding significance for synergistic inhibition. [ABSTRACT FROM AUTHOR]

A novel imidazoline derivative has been synthesized and its molecular structure has been confirmed by IR, Raman, elemental analysis and NMR, the molecular structure of the inhibitor is similar to that of the previous research. In this paper, the inhibition performance and inhibition mechanism of the three inhibitors (SMID, SMIS and SMIF) in concrete simulation solution are analyzed and compared. The corrosion inhibition efficiency of SMIF (96.02 %) > SMIS (93.62 %)>SMID(93.01 %) in weight loss experiment, the SMIS of electrochemistry of Nyquist and potentiodynamic polarization were 89.72 % and 92.03 % respectively, which indicated that SMIS had good corrosion inhibition effect. Electrochemical experiments show that the SMIS belongs to anodic type, and the mechanism of SMIS can form a protective film on the surface Q235 and inhibit the charge transfer. The results of FTIR, EDS and XPS show that SMIS can be adsorbed on the surface of Q235, which is also confirmed by density functional theory (DFT) and molecular dynamics simulation (MD). [ABSTRACT FROM AUTHOR]

• • BTTA exhibits more superior inhibition performance for steel corrosion than BTA due to S-linker. • • BTTA follows the characteristic of the mixed-type inhibitor. • • Theoretical modeling gives deep insights into adsorption and inhibition mechanism. Comparison of inhibition behavior of two tetrazole derivatives namely 5-(Benzylthio)-1H-tetrazole (BTTA) and 5-Benzyl-1H-Tetrazole (BTA) for Q235 steel in sulfuric acid has been investigated by electrochemical measurements, weight loss, FE-SEM, EDS, AFM, DFT, and molecular dynamics simulation. It is found that η values can reach 98.3% for 2 mM BTTA at 120 min, while BTA can only provide 21.6% in same condition. The significant promotion of inhibition performance corresponds to the existence of S-linker in the BTTA molecule, which induce the formation of stable multiple anchored BTTA layer on steel substrate. In other words, BTTA can exhibit more efficient chemical coordination ability with steel compared with BTA. The relevant action mechanism at molecular/atomic level was further analyzed based on Langmuir model and theoretical calculation. [ABSTRACT FROM AUTHOR]

• The inhibition effectiveness of nitrogen-containing organics on copper was proved. • Triazole derivatives have better anti-corrosion performance at low concentration. • DFT and MD simulation provide support for the experimental results. Corrosion inhibitors are added to the slurry to mitigate the excessive corrosion of copper in the chemical mechanical polishing (CMP) process, and their adsorption mechanisms will affect the corresponding inhibition efficiencies. A comprehensive study of several types of inhibitors in the weak alkaline H 2 O 2 -sarcosine solution found that the number of heteroatoms and the substitution behavior of amino groups in nitrogen-containing organics could improve their corrosion inhibition efficiencies. The electrochemical results showed that all the inhibitors were mixed-type except for BIT, which was an anodic inhibitor. The benzo derivatives could not provide favorable inhibition at low concentrations, while the triazole derivatives are free from this deficiency. When 0.5 wt% inhibitors were added to the blank solution respectively, the corrosion inhibition performances of benzo derivatives ranked as IND < BZA < BIT, and the order of inhibition efficiencies of triazole derivatives is TAZ < 3-ATA < 5-ATZ. The SEM images of the polished wafer surfaces coincided with electrochemical experiments. Quantum chemical calculations predicted the reactive sites of molecules. Molecular dynamics simulations showed that triazole inhibitors could be adsorbed in parallel in the aqueous environment, while the benzo inhibitor molecules presented a certain tilt with the Cu (1 1 1) surface. [ABSTRACT FROM AUTHOR]

• • Electrochemical test data indicate Pyracantha fortuneana alcohol extracts belong to mixed-type corrosion inhibitor. • • The Pyracantha fortuneana alcohol extracts adsorb on the Cu in accordance with the Langmuir model. • • Theoretical calculation provide in-depth understanding of the experimental results. Compared with traditional copper corrosion inhibitors, Pyracantha fortuneana alcohol extracts are derived from natural plants, will not cause environmental pollution after use, and are in line with the concepts of green chemistry and sustainable development. In this study, Pyracantha fortuneana alcohol extracts (PFAE) were obtained by ethanol soaking extraction method. PFAE, a novel degradable green corrosion inhibitor, has been investigated by experiments and theoretical calculations for its anti-corrosion performance of copper in H 2 SO 4 solution. Electrochemical experiments have demonstrated a pronounced increase in corrosion inhibition efficiency (η) as the concentration of PFAE rises. At a PFAE concentration of 600 mg/L, the inhibition efficiency can exceed 95 %. Additionally, the electrochemical method was used to investigate how the effect of soaked time on its anti-corrosion performance. After 4 h of immersion in a H 2 SO 4 solution containing PFAE, the copper could still maintain more than 80 % of the anti-corrosion performance. The results of surface morphology analysis demonstrate that after adding PFAE, the roughness of the copper sample is significantly reduced. This provides intuitively evidence that PFAE can indeed proficiently inhibit copper corrosion within a sulfuric acid solution. According to the study of the adsorption model, it was found that the adsorption behavior of PFAE onto the copper surface adheres to the Langmuir monolayer adsorption model. Moreover, the findings indicate the coexistence of both physical and chemical adsorption mechanisms. The findings of molecular dynamics simulations (MD) and quantum chemistry (QC) calculations indicate that the six active components of PFAE can display strong anti-corrosion capability. [ABSTRACT FROM AUTHOR]

During the polishing process of the cobalt (Co) interconnect layer, the corrosion inhibitor in the polishing solution will leave an organic residue on the polished cobalt surface, which needs to be removed by the post-chemical mechanical polishing (CMP) cleaning process. However, given the active chemical properties of cobalt, the potent and corrosive complexing agents in traditional cleaning solutions have the drawback of generating new corrosion defects on the cobalt surface. In this study, an eco-friendly cleaning solution is developed utilizing tetraethyl ammonium hydroxide (TEAH), deionized water, and either sarcosine or serine, thereby ensuring the absence of any additional introduction of metal impurities. The removal effect of the cleaning solution on BTA was tested using atomic force microscopy (AFM) and X-ray photoelectron spectrometer (XPS). The results demonstrate that post-CMP cleaning with either sarcosine or serine yielded a cobalt surface with reduced roughness (2.78 nm and 2.63 nm), diminished Co-BTA content (10.6% and 9.5%), and a lowered contact angle (44.3° and 37.9°). To elucidate the mechanism of post-CMP cleaning, electrochemical measurements and molecular dynamics were employed. Initially, in the cleaning solution with a pH of 10.4, the adsorption of BTA and cobalt is minimized. Subsequently, as serine permeates through the BTA residue layer, the desorption of BTA is expedited through competitive adsorption. These findings contribute valuable insights into the mechanism of residue removal in post-CMP cleaning processes. [Display omitted] • An eco-friendly, metal-free cleaning solution is proposed, incorporating organic bases and amino acids. • The surface roughness of the cleaned cobalt is 2.63 nm, and the surface is smooth without pitting corrosion. • Cleaning effect linked to complexing agent's adsorption capacity. • Mechanism of organic residue removal post-CMP cleaning analyzed through experiments and simulations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both DDA, DPD show excellent corrosion inhibition performance for cobalt. • Surface morphology of cobalt samples were examined by AFM and SEM. • The adsorption process of DDA, DPD follows Langmuir adsorption isotherm. • Experimental results were supported by DFT and molecular dynamics simulations. • The solubility and toxicity of DDA, DPD were evaluated by theory. Cobalt, as the barrier layer material for 14 nm copper interconnection, has been widely applied owing to its superior characteristics of low resistivity, excellent adhesion performance and blocking properties for copper. Most of the preciously developed cobalt corrosion inhibitors under weak alkaline condition are toxic, low water solubility, and limited to traditional experimental research. In this work, 3,3-dithiodipropionic acid (DDA), 2,2-dibenzamidodiphenyl disulfide (DPD) as potential corrosion inhibitors for cobalt in NH 4 Cl and H 2 O 2 media under alkaline environment were investigated. Electrochemical experiments, surface morphology characterization, quantum chemical calculation and molecular dynamic simulation were combined to analyze the corrosion inhibition ability and mechanism. The experimental and theoretical results present that these disulfide derivatives can inhibit the corrosion behavior of cobalt surface effectively in ammonium-based aqueous solutions. When the concentration of inhibitors was 0.5 wt%, the corrosion inhibition efficiency of DDA, DPD reach up to 92.9%, 91.41%, respectively. Their favorable capability is attributed to the dense adsorption films following the Langmuir adsorption isotherm. Besides, these two inhibitors show excellent performance of galvanic corrosion inhibition at the Co/Cu interface, which is consistent with the shift tendency simulations for binding to Co/Cu substrates. The results of water solubility and toxicity tests indicate that DDA is more suitable for industrial applications. [ABSTRACT FROM AUTHOR]

• The solubility and toxicity of PO were evaluated by theory. • PO shows excellent corrosion inhibition performance on Cu in EDTA-H 2 O 2 based system under alkaline condition. • The adsorption process of PO on Cu follows Langmuir adsorption isotherm. • Surface morphology of Cu surface was examined by SEM and AFM. • Experimental results were supported by DFT and molecular dynamics calculations. The application of corrosion inhibitors is one of the most effective methods developed to inhibit the corrosion of Cu interconnects. The performance of potassium oleate (PO) as a potential corrosion inhibitor for copper in EDTA-H 2 O 2 based solution was examined under alkaline environment. The inhibition efficiency and mechanism were studied by electrochemical characterization, surface morphology technology and molecular computing technology. Firstly, the water solubility and toxicity of PO were comprehensively evaluated. The results of electrochemical assessment manifest that the corrosion inhibition efficiency of PO for Cu can reach approximately 98.24%, even at relatively low concentration of PO (0.01 wt%), additionally, PO is a mixed-type corrosion inhibitor, which can effectively inhibit the corrosion circumstance of Cu in alkaline medium. These excellent performances are attributed to the physical and chemical properties of PO adsorption films formed by PO, which follows the Langmuir adsorption isotherm. Besides, Density Functional Theory (DFT) and molecular dynamics (MD) approaches were introduced to explore the most stable adsorption configuration and the most active adsorption sites. [ABSTRACT FROM AUTHOR]

2-amino-6-bromobenzothiazole (ABBT) as an inhibitor of copper corrosion in 0.5 M H2SO4 solution was researched in this study using with electrochemical measurement, scanning electron microscope, atomic force microscope, and theoretical calculation. Polarization curves manifest that ABBT acts as a modest cathodic-type inhibitor with a maximum achievable inhibition efficiency of 94.6% at 1 mM. EIS test indicates that ABBT adsorb on the copper surface and form an adsorption film, which obeys Langmuir adsorption model. Furthermore, DFT calculation and molecular dynamics simulation were utilized to explore the mechanism of inhibition of ABBT. [ABSTRACT FROM AUTHOR]

In this computational study, the adsorption and corrosion inhibition properties of some novel quinoline derivatives namely, 2-amino-7-hydroxy-4-phenyl-1,4-dihydroquinoline-3-carbonitrile (Q1), 2-amino-7-hydroxy-4-( p -tolyl)-1,4-dihydroquinoline-3-carbonitrile (Q2), 2-amino-7-hydroxy-4-(4-methoxyphenyl)-1,4-dihydroquinoline-3-carbonitrile) (Q3) and 2-amino-4-(4-(dimethylamino)phenyl)-7-hydroxy-1,4-dihydroquinoline-3-carbonitrile (Q4) on the corrosion of iron were investigated using quantum chemical and molecular dynamics simulation approaches. Quantum chemical calculations section of the study provides enough calculation and discussion on the relationship between corrosion inhibition and global reactivity descriptors such as E HOMO , E LUMO , HOMO-LUMO energy gap (ΔE), chemical hardness (η), softness (σ), electronegativity (χ), chemical potential (μ), electrophilicity (ω), nucleophilicity (ɛ), electrons transferred from inhibitors to metal surface (ΔN), initial molecule–metal interaction energy (Δψ), total electronic energy (E), the energy change during electronic back-donation process (ΔE b-d ). The adsorption behaviors of studied compounds on Fe (110) surface were investigated with the help of molecular dynamics simulation approach. The binding energies calculated on Fe (110) surface of mentioned quinoline derivatives followed the order: Q4 > Q3 > Q2 > Q1. It should be noted that the results obtained in the study are in good agreement with experimental inhibition efficiency results earlier reported. [ABSTRACT FROM AUTHOR]

[Display omitted] • The inhibition effect of traditional corrosion inhibitor BTA on cobalt pitting is not ideal. • The molecules of MBTA and TT-LYK have stronger electron donating ability than BTA. • The passivation films formed by MBTA and TT-LYK are more hydrophobic than BTA. • TT-LYK can protect cobalt from pitting in corrosive environmental. As integrated circuits shrink in feature size to 10 nm, the requirements of pitting defects on the cobalt (Co) surface become more stringent during the chemical mechanical polishing of Co interconnects. In this work, the corrosion inhibition effects of benzotriazole (BTA) and its two derivatives, 5-methyl benzotriazole (MBTA) and 2,2′-[[(methyl-1H-benzotriazol-1-yl)methyl]imino]bis-Ethanol (TT-LYK) in the slurry at pH 9 were studied by electrochemical methods, contact angle measurement, and scanning electron microscopy (SEM). The adsorption process of the three inhibitors on the cobalt surface could be described by the Langmuir isotherm model. All the azole corrosion inhibitors belong to anodic corrosion inhibitors for Co in a weak alkaline environment. When 8 mM BTA, MBTA and TT-LYK was added to the base solution containing 0.15 wt% glycine and 0.5 wt% H 2 O 2 , respectively, the corrosion inhibition efficiency reached 87.67%, 92.63% and 95.38%. In addition, the SEM results show that there are almost no pitting defects on the Co surface protected by TT-LYK. Furthermore, the quantum chemical parameters of the three inhibitors were calculated by molecular dynamics and density functional theory. The experimental data support the results of the density functional theory and Molecular dynamic simulation. [ABSTRACT FROM AUTHOR]

• Ranunculus bulbosus extract was used as a new environmentally-friendly corrosion inhibitor of MS exposed to 1 M HCl solution. • Using 2000 ppm Ranunculus bulbosus extract resulted in 94% corrosion inhibition efficiency according to EIS test results. • The inhibitor showed mixed inhibition and its adsorption obeyed a Langmuir isotherm. • Molecular simulations associated with DFT modeling highlighted the green ingredients adsorption on the steel. Owing to the movement toward greener earth, this study is a small contribution to this global process. The current research selected the Ranunculus bulbosus (RB) molecules in order to evaluate whether its extract could impart a corrosion-preventive quality to the MS attribute in the HCl condition. To reach this point, some distinct, as well as related tests, were performed. FESEM and AFM confirmed the positive impact of RB extract (RBE) upon the microstructure; the RBE addition considerably smoothened the surface in contrast with the sample doped with no RBE. UV–Vis showed the presence of several functional groups on the surface; while GIXRD provided the reason for the possible complexation of RBE molecules with Fe. Raman test confirmed the presence of inhibitor molecules on the surface via analyzing the carbon-based structures' existence. EIS was used for the corrosion-related analysis, and the increment of inhibitor concentration to 2000 ppm in company with 5 h of drowning time maximized the potency of corrosion resistance to 94%. Also, the corrosion-preventive performance of the RBE was supported by potentiodynamic polarization tests. RBE adsorbed over the surface via Langmuir regulation. Quantum chemical calculations based on the density functional theory (DFT) and molecular dynamics (MD) simulation have delivered helpful information regarding electron transfer and mechanism during adsorption of inhibitor ingredients on the mild steel surface. MD simulation revealed the interaction of inhibitors molecules and surface in addition to their high coverability. Also, DFT results suggested that electron sharing could occur between inhibitors molecules as metallic surfaces. In the end, the comparison of other studies with the current one was provided, and the mechanism was discussed. [ABSTRACT FROM AUTHOR]

The adsorption of glycine, glutamic acid, histidine and phenylalanine on single-layer graphdiyne/ graphene is investigated by ab initio calculations. The results show that for each amino acid molecule, the adsorption energy on graphdiyne is larger than the adsorption energy on graphene and dispersion interactions predominate in the adsorption. Molecular dynamics simulations reveal that at room temperature the amino acid molecules keep migrating and rotating on graphdiyne surface and induce fluctuation in graphdiyne bandgap. Additionally, the photon absorption spectra of graphdiyne-amino-acid systems are investigated. We uncover that the presence of amino acid molecules makes the photon absorption peaks of graphdiyne significantly depressed and shifted. Finally, quantum electronic transport properties of graphdiyne-amino-acid systems are compared with the transport properties of pure graphdiyne. We reveal that the amino acid molecules induce distinct changes in the electronic conductivity of graphdiyne. The results in this paper reveal that graphdiyne is a promising two-dimensional material for sensitively detecting amino acids and may potentially be used in biosensors. [ABSTRACT FROM AUTHOR]

Abstract: Research on the molecular flow transmission probabilities of tubes is important in vacuum science and technology, as well as in some special applications in space technology. This study examines an algorithm based on Monte Carlo method to calculate the molecular flow transmission probabilities of any regular polygon tubes. This method fully utilizes the symmetries of regular polygons to simplify calculation. The results show that when the cross-sectional areas and lengths L of tubes remain constant, the molecular flow transmission probabilities of regular polygon tubes increase and approach those of cylindrical tubes with an increase in the number of sides. Moreover, any regular polygonal or cylindrical cross-section tube has nearly the same transmission probability within 2.8% of the maximum difference in the range of L ≤ 100 (the cross-sectional area of each tube is π). [Copyright &y& Elsevier]

The novelty of the work is to investigate the application of two new epoxy resins namely as hexaglycidyl N-phenylaminopropoxy-N.N.N-triphenyl propane-1.3-diamine (ERH) and octaglycidyl N.N.N.N-tetraphenylamino-N.N.N.N-tetrapropoxy methylene dianiline (ERO) as potential corrosion inhibitors for carbon steel (CS) in 1 M HCl medium. The corrosion resistance was quantified by various techniques namely polarization curve (PC), electrochemical measurement (EIS), scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS), global quantum chemical descriptors (GQCDs) and molecular dynamics (MDs) simulation. EIS data suggest that the corrosion efficiency of ERO (94.1%) is higher than that of the ERH (89.7%) in HCl medium at room temperature. Further, PC results indicate that the corrosion efficiency of ERO (95.6%) is higher than that of the ERH (95.4%) in the presence of 10−3 M of studied inhibitors and also PC data suggest that the two epoxy resins investigated acted as a mixed type inhibitor. Langmuir adsorption isotherm is the most acceptable technique or method to describe the ERH and ERO epoxy resins adsorption on the CS area. SEM/EDS data display the two ERH and ERO epoxy resins can be stopped the acid attack though chemisorption on the CS surface. GQCDs calculations were applied by density functional theory (B3LYP and WB97XD) and Hartree-Fock (HF) methods using 6-31G(d,p) basis sets to study the inhibition efficiencies of the two epoxy resins inhibitors. GQCDs such as E HOMO , E LUMO , energy gaps, electronegativity, hardness, electrophilicity, fractions of electron transferred were calculated and discussed. Other energetic parameters such the free energy of adsorption, the metal-inhibitor energy gaps, the electron transfer back-donation energy and the initial molecule-metal interaction energy were also calculated and discussed. The molecular dynamics simulation approach was performed to investigate the adsorption behaviors of the investigated inhibitors on Fe(110) surface. The results obtained using the computational methods and the molecular dynamics simulations reveal that the ERO inhibitor has more inhibitory effect against corrosion of the Fe-metal than that of the ERH inhibitor. The obtained theoretical results were adapted with experimental inhibition efficiency results. [Display omitted] • Two epoxy resins (ERH and ERO) were synthesized and investigated as potential anticorrosive protection. • Corrosion efficiency of ERO is higher than that of the ERH in HCl solution. • SEM/EDS analysis displayed the both ERH and ERO inhibitors could effectively block the acids attack by chemisorption. • Theoretically approaches are in good agreement with experimental data. [ABSTRACT FROM AUTHOR]

• A newly benzimidazole derivative has been synthesized and characterized. • Its structural is confirmed by XRD and compatible with DFT findings. • The compound exhibited promising NLO properties. • Molecular docking and molecular dynamics studies were performed for the compound. The present article describes the synthesis of the new compound 2-methylbenzimidazo[1,2- a pyrimidin-4(1 H)-one. The electronic and spatial structure of this molecule was studied theoretically and experimentally. The title molecule, C 11 H 9 N 3 O, is slightly twisted and bowed based on the recent crystallographic study, while the DFT-B3LYP study shows that the title compound is fully planar in the gas phase. This discrepancy between the experimentally determined geometry and the B3LYP optimized one may be due to the crystal packing. In the crystal, a layer structure is formed by N—H•••N and C—H•••O hydrogen bonds together with π-stacking and C—H•••π(ring) interactions. However, the Hirshfled surface analysis showed that the most important intermolecular interaction for the title compound is the H•••H contact. Based on the wide biological interest, molecular docking and molecular dynamics studies were performed for the above titled compound with the poly(ADP-ribose)polymerase (PARP) enzyme target and the result shows that there is a good binding affinity and stability in PARP complex system. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • TODTI was investigated as a green and effective corrosion inhibitor. • TODTI inhibitor indicated a high efficiency of 96.72% at 200 mg/L. • The inhibitor adsorbs on steel surface following Langmuir isotherm. • PDP results confirmed that TODTI is a mixed type of inhibitor with anodic dominance. • Theoretical investigations suggested the better performance of the protonated form of inhibitor. The new and eco–friendly corrosion inhibitor based on thioglycoluril derivative (2–thioxo–5,5–di–p–tolylimidazolidin–4–one (TODTI)) for St2 steel in 1 M HCl + 1 M Na 2 SO 4 solution was first introduced and its inhibition properties were first fully characterised by gravimetric, thermodynamic, potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), electrochemical noise (EN), electrochemical frequency modulation (EFM), density functional theory (DFT), molecular dynamics (MD) simulations, scanning electron microscopy (SEM) and energy dispersive X–ray spectrometry (EDX) methods. The effect of thioglycoluril rings on the St2 steel inhibition and salt–corrosion on the St2 steel surface was first studied. The experimental results indicated that TODTI had excellent inhibition abilities (96.72% at 200 mg/L/0.675 mM) at medium temperatures (303–333 K); the St2 steel was maximally inhibited and salt–corrosion was importantly reduced with the adsorption of thioglycoluril rings on the metal surface in the aggressive hydrochloric acid with sulfate ions. The electrochemical investigations revealed that TODTI is a mixed–type corrosion inhibitor, and its adsorption nature was confirmed according to the Langmuir isotherm. The quantum chemical calculations confirmed a good correlation with the experimental results and indicated that the inhibitory nature of TODTI is linked to its quantum chemical characteristics. [ABSTRACT FROM AUTHOR]

[Display omitted] A great deal of consideration has been given to the development of new compounds having diverse functionality. In this report, a new indazole derivative bearing a nitro group, namely 2-(3-chloro-5-nitro-1 H -indazol-1-yl) acetic acid (CNIA) was synthesized, characterized, and used as corrosion inhibitor for mild steel (MS) in 1.0 M HCl. A full characterization of the prepared compound was performed using single‐crystal XRD, FT-IR, and UV–vis measurements; its corrosion inhibition properties were experimentally evaluated by potentiodynamic polarization (PDP) curves as well as electrochemical impedance spectroscopy (EIS) measurements, and theoretically by Density Functional Theory (DFT) and molecular dynamics (MD) simulations. Scanning electron microscope (SEM) was used to examine the morphology of the corroded metal surface before and after the inhibition. The findings demonstrated that the application of CNIA significantly reduced the corrosion rates of MS. The corrosion inhibition ability of the synthesized compound was also identified at a lower concentration in all experiments, reaching a maximum of 89 % at 10−3 mol/L. The results of potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) confirmed that CNIA could be categorized as a mixed type inhibitor with an increased polarization resistance at higher concentrations. Langmuir's adsorption isotherm was found to fit the adsorption of CNIA molecules on the MS surface. SEM photographs showed obvious less-corroded morphologies in the presence of the CNIA as compared to untreated MS surface. Theoretical calculations were proposed to explain the mechanism of the inhibition effect and found that it is due to the donor/acceptor properties of the inhibitor and its parallel disposition over the steel surface. The present compound could be a promising corrosion inhibitor for mild steel in HCl solutions, and showed a corrosion inhibition property that is superior to similar compounds. [ABSTRACT FROM AUTHOR]

• ACDs exhibited good efficiency in acidic solution. • Simulations showed excellent correlation with experimental data. • EFM showed potential mitigation of steel by ACDs at 600 mg/L. • SEM and AFM confirmed inhibitor/metal complex formation. Two new acridinedione namely 3,3,6,6-Tetramethyl-9,10-diphenyl-3,4,6,7,9,10-hexahydro-1,8-(2H,5H)-acridinedione (ACD-1), and 9-(4-methoxyphenyl)-3,3,6,6-tetramethyl-10-phenyl-3,4,6,7,9,10-hexahydroacridine-1,8(2H,5H)-dione (ACD-2) were synthesized and tested as prominent inhibitors for N80 steel corrosion inhibition in 15% hydrochloric acid (HCl). The weight loss result showed maximum efficiency of 97.3% (ACD-2) and Langmuir isotherm model best explained the adsorption of ACDs. EIS study reveals R ct value increased to a maximum of 816.4 Ωcm2 with the inhibition efficiency of 95.6% at 600 mg/L (ACD-2). The results of PDP proposed that ACDs are mixed but cathodic dominance inhibitors. The scanning electron microscopy (SEM) and atomic force microscopy (AFM) tests supports the adsorption of ACDs molecules onto the N80 steel surface. Intermolecular interactions and dynamics were studied using density functional theory (DFT) and molecular dynamics (MD). [ABSTRACT FROM AUTHOR]

The anti-corrosion potency of three synthesized 8-hydroxyquinoline derivatives, namely 5-(azidomethyl)-7-(morpholinomethyl)quinolin-8-ol (HM1), 2-(8-hydroxy-7-(morpholinomethyl)quinolin-5-yl)acetonitrile (HM2), 5-(azidomethyl)-7-(piperidin-1-ylmethyl)quinolin-8-ol (HM3) in hydrochloric acid for mild steel was investigated using weight loss and electrochemical techniques. Potentiodynamic polarization (PDP) data reveal that all three compounds were cathodic inhibitors, with HM3 presentation significant mixed-type effect at high inhibitor concentrations (10−3 M). Electrochemical impedance spectroscopy (EIS) data reveal better adsorption of compounds species on MS surface at increased inhibitor concentrations with HM1 , HM2 and HM3 reaching a maximum efficiency of 90, 89 and 88%. The three compounds HM1 , HM2 and HM3 were inclined towards the Langmuir adsorption-isotherm by spontaneous chemical-physical adsorptions of inhibitors on the mild steel surface. The correlation between the electronic properties and inhibition efficacies of the tilted inhibitors was determined by using simple linear regression technique. Electronic properties were calculated for neutral and protonated forms in a polarizable continuum model using the DFT method at the B3LYP/6–311 + G (d, p) level of theory. The active adsorbed sites of HM1 - HM3 on the metal surface were determined by analyzing their corresponding electrostatic surface potentials (ESP). Furthermore, molecular dynamics simulations have been performed to illustrate the most conceivable adsorption configuration between the inhibitors and metal surface. Unlabelled Image • Synthesis and investigation of the corrosion inhibition of three 8-hydroxyquinoleine derivatives. • The adsorption of inhibitors obeys Langmuir adsorption isotherm. • DFT modelling and Molecular dynamics simulations provided molecular level insights. • Correlation between the corrosion inhibition and quantum chemical and molecular dynamic stimulation results. [ABSTRACT FROM AUTHOR]

2,2′-Dithiosalicylic acid (DSA), 2-aminophenyl disulfide (APD) and 2,2-dibenzamidodiphenyl disulfide (DPD) were determined for corrosion inhibition of Cu in H 2 SO 4 media by electrochemical tests, surface morphology analysis, quantum chemical calculations and molecular dynamics simulations. The results of polarization curves showed that DSA, APD and DPD reveal good anti-corrosion capacity. They can simultaneously inhibit the cathodic and anodic reactions of copper. Therefore, they belong to the mixed-type corrosion inhibitors. Impedance spectroscopy results showed that when DSA, APD and DPD adsorption on the surface of Cu, the charge transfer resistance increases significantly and typical capacitance behavior produced, which indicates that the formed inhibitor film is very dense and ordered. In addition, the adsorption of corrosion inhibitors on the Cu surface is conforming to Langmuir monolayer adsorption. The experimental results obtained by surface topography analysis are consistent with the results of electrochemical experiments. Their corrosion inhibition ability is DSA < APD < DPD. Theoretical calculations further explore the relationship between corrosion inhibition performance and their molecular configurations. • Electrochemical test data indicates that the inhibition efficiency is DSA < APD < DPD. • The DSA, APD, and DPD adsorb on the Cu surface in accordance with the Langmuir model. • Quantum chemistry research and molecular dynamics simulation provide in-depth understanding of the experimental results. [ABSTRACT FROM AUTHOR]