Novel cationic aryl bithiophene/terthiophene derivatives as corrosion inhibitors by chemical, electrochemical and surface investigations

Enhancing Al-Air Battery Performance with Beta-d-Glucose and Adonite Additives: A Combined Electrochemical and Theoretical Study

Al-air batteries are distinguished by their high theoretical energy density, yet their broader application is hindered by hydrogen evolution corrosion. This research focuses Beta (+) d-glucose (S1) and Adonite (S2) as potential corrosion inhibitors for the Al-5052 alloy within a 4 M NaOH solution. Utilizing electrochemical techniques, hydrogen evolution assessments, and surface analyses, our findings indicate enhancements in anode utilization by 21.9% for S1 and 21.1% for S2. Inhibition efficiency reached 65.5% for S1 and 65.1% for both additives at a concentration of 10-3 M. Additionally, the introduction of S1 and S2 markedly increased the nominal specific capacity (654 mA h g-1 for S1 and 629 mA h g-1 for S2) and energy density (1922 W h kg-1 for S1 and 1849 W h kg-1 for S2) of the batteries. These results suggest that managing the electrolyte composition with these additives can significantly enhance battery performance in alkaline environments. Supporting our experimental findings, density functional theory (DFT) and molecular dynamics (MD) analyses confirmed improved anode passivation and beneficial molecular interactions, contributing to the reduction of corrosion in the Al-5052 alloy.

Electrochemical and DFT insights into 2-amino-4-(4-hydroxy-3-methoxyphenyl)-7-methyl-4H-chromene-3-carbonitrile: an innovative strategy for antibacterial activity and corrosion protection of carbon steel

This study explored the potential of a newly synthesized derivative, 2-amino-4-(4-hydroxy-3-methoxyphenyl)-7-methyl-4H-chromene-3-carbonitrile (AHMCC), as a broad-spectrum antibacterial agent and a corrosion inhibitor for carbon steel (C.STL) in 0.5 M HCl solution. AHMCC demonstrated remarkable antibacterial efficacy against Gram-negative (Escherichia coli, Klebsiella pneumoniae) and Gram-positive (Bacillus subtilis, Staphylococcus aureus) bacteria, as evidenced by agar plate tests and cell viability assays. In the corrosion inhibition studies, AHMCC exhibited mixed-type inhibitor behavior as revealed by potentiodynamic polarization (PDP) measurements. The inhibition efficiency increased with rising AHMCC concentration, confirmed by a significant enhancement in charge transfer resistance (R ct) observed in electrochemical impedance spectroscopy (EIS) analysis. Electrochemical frequency modulation (EFM) data with obtained CF2 and CF3 values further corroborated these findings. Langmuir isotherm modeling suggested AHMCC molecules followed a monolayer adsorption pattern on the C.STL surface. UV-visible spectroscopy indicated the formation of a protective layer through chemical interaction between AHMCC and the metal surface. Atomic force microscopy (AFM) provided visual confirmation of this protective film shielding the C.STL from the corrosive environment. Additionally, theoretical calculations supported the proposed adsorption mechanism of AHMCC molecules onto the C.STL surface.

Eco-Friendly Piper cubeba Official Extract Corrosion Inhibition of C-Steel in 1 M Sulfamic Acid

This work offers a high-performing, environmentally friendly corrosion inhibitor for carbon steel in 1 M sulfamic acid (H2NSO3H). Potentiodynamic polarization and electrochemical impedance spectroscopy were used to evaluate the anticorrosion properties of Pipper cubeba official extract (P.cubebaOE) for carbon steel in 1 M H2NSO3H at 25 to 45 °C. At a temperature of 45 °C, the P.cubebaOE reached a maximum corrosion inhibition efficiency of 96%. P.cubebaOE was also subjected to Fourier transform infrared spectroscopy in order to ascertain its primary chemical composition. Additionally, the behavior of P.cubebaOE in terms of corrosion inhibition on carbon steel was examined at the microscopic level using scanning electron microscopy. The findings demonstrate that P.cubebaOE's adsorption type on carbon steel conforms to the Langmuir adsorption isotherm model. Based on the adsorption isotherm model, the free energy was estimated to be approximately -20.0 kJ/mol, suggesting that P.cubebaOE is physically adsorbing on the surface of carbon steel. The results of the density functional theory and molecular dynamics simulations show that P.cubebaOE exhibits excellent inhibition performance on carbon steel in H2NSO3H solution and are consistent with the electrochemical experimental results. This work offers significant information on the development of environmentally friendly corrosion inhibitors for carbon steel.

Novel biphenylidene-thiopyrimidine derivatives as corrosion inhibitors for carbon-steel in oilfield produced water

The inhibiting efficiency of three newly synthesized organic compounds:5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)-1,3-diethyl-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (HM-1228), 5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (HM-1227) and 5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)pyrimidine-2,4,6(1H,3H,5H)-trione (HM-1226) in oilfield produced water on the corrosion of carbon steel has been examined via electrochemical measurements; potentiodynamic polarization (PDP) and electrochemical impedance (EIS) techniques. The adsorption of these compounds on the surface of carbon steel followed Langmuir isotherm. In addition, the surface morphology of uninhibited and inhibited carbon steel was examined by Atomic Force Microscopy (AFM), observing surface improvement when carbon steel samples exposed to the inhibited corrosive solutions. The average surface roughness (Ra) in oilfield produced water solution in the presence of 0.5 mM of HM-1228 inhibitor was 138.28 nm compared to the uninhibited surface 571.62 nm. To explore the corrosion inhibition mechanism, quantum chemical calculations and Monte Carlo simulations were utilized. The HM-1228 inhibitor demonstrated the highest corrosion inhibition efficiency at 94.8% by PDP measurements. The higher corrosion inhibition of compound HM-1228 can be attributed to the presence of di-N-ethyl groups that enhance both electron donating ability and lipophilic properties.

Design, synthesis, and performance evaluation of TiO2-dye sensitized solar cells using 2,2'-bithiophene-based co-sensitizers

We report on the synthesis and characterization of six novel 2,2'-bithiophene-based organic compounds (3a-c and 5a-c) that are designed to serve as co-sensitizers for dye-sensitized solar cells (DSSCs) based on TiO2. The compounds are linked to various donor and acceptor groups, and we confirm their chemical structures through spectral analyses. Our focus is on enhancing the performance of metal based N3, and the compounds were designed to operate at the nanoscale. We performed absorption and fluorescence emission measurements in dimethylformamide (DMF), where one of our compounds 5a exhibited the longest maximum absorption and maximum emission wavelengths, indicating the significant impact of the para methoxy group as a strong electron-donating group. Our dyes 5a + N3 (η = 7.42%) and 5c + N3 (η = 6.57%) outperformed N3 (η = 6.16%) alone, where the values of short current density (JSC) and open circuit voltage (VOC) for these two systems also improved. We also investigated the charge transfer resistance at the TiO2/dye/electrolyte interface using electrochemical impedance spectroscopy (EIS), which is important in the context of nanotechnology. According to the Nyquist plot, the 5a + N3 cocktail exhibited the lowest recombination rate, resulting in the highest VOC. Our theoretical calculations based on density functional theory (DFT) are also in agreement with the experimental process. These findings suggest that our compounds have great potential as efficient DSSC co-sensitizers. This study provides valuable insights into the design and synthesis of new organic compounds for use as co-sensitizers in DSSCs based on TiO2 and highlights the potential of these compounds for use in efficient solar energy conversion.

Construction, Characterization, DFT Computational Study, and Evaluation the Performance of Some New N-Amino Pyridinone Schiff Base Catalyzed with Ceric(IV) Ammonium Nitrate (CAN) as Corrosion Inhibitors in Some Petroleum Applications

In this paper, two novel organic inhibitors, TAP-TPP and TAP-CEQ, were prepared via Schiff base condensation as a green chemistry methodology using an eco-friendly catalyst, ceric ammonium nitrate, with a high yield (87% and 91%), and characterized via elemental analysis, FTIR, 1H, and 13C NMR spectroscopic analysis tools. Weight loss assessment was utilized as a chemical testing method, and the maximum inhibition efficiency of TAP-TPP and TAP-CEQ is 89.4% and 91.8%, respectively. PDP and EIS were electrochemical measures to determine the efficacy of both inhibitors as anticorrosion for carbon steel alloys in 2 M HCl aggressive media. The collected electrochemical results demonstrated that both inhibitors behaved as excellent anticorrosion agents for metallic constructions. According to the potentiodynamic polarization (PDP) analysis, these organic inhibitors worked as mixed-type inhibitors. The adsorption isotherm revealed that undertaken compounds obeyed Langmuir adsorption isotherm with the free energies of adsorption of ranged from ΔG = − 34.29 to − 34.63 kJ Mol−1. Also, electrochemical impedance spectroscopy (EIS) data confirmed that the values charge transfer resistance (Rct) was increased by increasing the concentration of the injected inhibitor molecules. In contrast, the electrochemical double layer (Cdl) was dramatically decreased. The work was supported by two-surface analysis methods such as SEM and EDX. For more details, the values of percentage inhibition efficiency can be ordered as follows: TAP-CEQ > TAP-TPP. Finally, a suitable inhibition mechanism and theoretical studies including EHOMO, ELUMO, diploe moment (µ), and electrophilicity index (ω) were assumed and discussed in detailed.

Preparation of zwitterionic ionic surfactants-based sulphonyl for steel protections: Experimental and theoretical insights

Designating an organic inhibitor with a specific chemical structure that actively participates in steel protection by increasing adsorption on the steel surface. Based on that, we synthesized three zwitterionic surfactants based on azomethine with different hydrophobic chain lengths labeled ZWSO, ZWSD, and ZWSH. The presence of azomethine group, electrons, and heteroatoms in the zwitterionic surfactant’s amphipathic structure helped to improve C-steel protection. Their inhibitory activity toward steel corrosion was investigated utilizing electrochemical impedance spectroscopy (EIS), gravimetrical, and potentiodynamic polarization techniques. Importantly, the surfactant tail influenced corrosion inhibition performance; as surfactant tail length increased, so did inhibition efficiency due to increased adsorption affinity. The inhibition efficiencies of ZWSO, ZWSD, and ZWSH are 87.15, 89.82, and 91.36%, respectively. Tafel data clarified that ZWSO, ZWSD, and ZWSH inhibitors behave as mixed-type inhibitors following the modified Langmuir isotherm. The inhibitors can adsorb physiochemically on the steel surface with ∆G ads ranges from −38.48 to −44.6 kJ mol−1. The SEM confirms that the morphology of C-steel becomes smoother because of inhibitor adsorption. The DFT and MCs output data supported the experimental performance of the tested ZWSO, ZWSD, and ZWSH inhibitors and especially their dependence on surfactant tail length.

Suppression of steel corrosion via some gemini cationic surfactant-based Schiff base: experimental and theoretical investigations

Steel is involved extensively in engineering vast constructing units in many industries and can undergo to corrosion by some chemical and/or electrochemical reactions with the environment. Therefore, designating an organic inhibitor with a specific chemical structure will participate in steel protection via enhancing their adsorption on the steel surface. Three gemini cationic surfactants based on azomethine with different hydrophobic tails labeled GSBI8, GSBI12, and GSBI16 have been designated and evaluated as corrosion inhibitors utilizing electrochemical impedance spectroscopy (EIS), gravimetrical and potentiodynamic polarization techniques. Importantly, the surfactant tail regulated the corrosion inhibition performance; with increasing the surfactant tail length, their inhibition efficiency enhanced because of their higher adsorption affinity. The inhibition efficiency of GSBI8, GSBI12, and GSBI16 reached 95.52, 96.72, and 97.1% respectively (EIS measurements). The Tafel examination clarified that GSBI8, GSBI12, and GSBI16 inhibitors behave as mixed type inhibitors following the modified Langmuir isotherm. The inhibitors adsorption on C-steel was confirmed by SEM surface examination. Finally, the DFT and MCs point of views investigation supported the experimental performance of the tested GSBI8, GSBI12, and GSBI16 inhibitors and specially their dependence on surfactant tail length.

The Role of Some Cationic Surfactants Based on Thiazine as Corrosion Inhibitors in Petroleum Applications: Experimental and Theoretical Approach

Two cationic surfactants based on thiazine, dodecyl thiazin bromide (DTB) and hexyl thiazin bromide (HTB), were synthesized, characterized, and investigated as corrosion inhibitors for API X-65 type steel in oil wells' formation water under an H₂S environment. Various spectroscopic techniques such as FTIR and ¹H NMR were used to confirm the DTB and HTB chemical structures. The corrosion inhibition efficiency of the selected compounds was investigated using both potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The innovation of the current study is the existence of a long chain in the inhibitor molecule, which leads to an increase in the performance of the surfactant as a corrosion inhibitor, due to the increase in the surface area per molecule. It was found that these surfactants act as mixed-type inhibitors, leading to suppression of both the cathodic and the anodic processes by its adsorption on the electrode surface according to the Langmuir adsorption isotherm. Carbon steel's inhibitory mechanism was studied using an analogous circuit. The scanning electron microscope technique was used as a suitable analysis tool to show the nature of the layer designed on carbon steel. Quantum chemical calculations and Monte Carlo simulation techniques were used to support the obtained experimental results. Finally, a suitable mechanism for the inhibition process was proposed and discussed.