Anticorrosion Efficiency Research Articles

Electrodeposition of Zinc–Nickel Coatings from Glycine-Containing Ammonium-Chloride Electrolyte

The kinetic regularities of the electrodeposition process of alloyed zinc–nickel coatings from an ammonium-chloride electrolyte solution have been studied. The effect of the addition of aminoacetic acid on the mechanism of the electrodeposition process, current efficiency, surface morphology, chemical and phase composition of the synthesized coatings has been established. The process of electrochemical deposition of alloys of Zn–Ni system from ammonium-chloride electrolyte is complicated by the diffusion transport of ions in the liquid phase of the electrolyte solution, while the kinetic stage of charge transfer is irreversible. The addition of aminoacetic acid does not change the mechanism of the electrodeposition process, however, it increases the current efficiency of the target process by approximately 6%, presumably due to a decrease in the contribution of the hydrogen evolution reaction to the overall rate of the cathodic process. The addition of glycine improves the surface morphology of the synthesized coatings by reducing the roughness and denser packing of the nuclei of the growing phase, and also increases the nickel content in the alloy by an average of 4 at %, but does not affect the phase composition of the coatings, which remain heterogeneous and consist of γ-phase of Ni2Zn11 and Zn. A quantitative assessment of the anticorrosive efficiency of electrodeposited zinc–nickel alloys is carried out depending on the presence of aminoacetic acid in the electrolyte solution. It is found that the introduction of glycine into ammonium-chloride electrolyte of deposition leads to the refinement of the corrosion potential and a noticeable decrease in the corrosion current density of the Zn, Ni-alloy coating in aqueous solution of 3.5% NaCl. This indicates an increase in the resistance of the electrochemically synthesized protective film material to corrosion damage. The optimal conditions for the electrochemical synthesis of morphologically homogeneous anticorrosive zinc–nickel coatings are selected.

Effects of Ultrafine Bismuth Powder on the Properties of Zinc Electrodes in Zinc-Air Batteries

Ultrafine spherical zinc powder prepared by direct-current arc plasma evaporation increased the capacity and life of zinc-air batteries. To decelerate the corrosion of the ultrafine zinc powder and improve the charge–discharge performance of the zinc-air batteries, we added different amounts of ultrafine bismuth powder to a zinc electrode. The hydrogen evolution rate of the Zn-Bi electrode and the properties of zinc-air batteries were investigated by hydrogen evolution experiments and electrochemical performance tests. The corrosion inhibition mechanism of the newly added bismuth powder on the zinc electrode was studied via x-ray diffraction, scanning electron microscopy and x-ray photoelectron spectroscopy. The results show that when the amount of the ultrafine bismuth powder was 1.5 wt.% of the zinc powder, the anticorrosion efficiency of the Zn-Bi electrode was the highest, reaching 53.8%. After the battery assembly, the Zn-Bi electrode reached a capacity retention rate of 84.6% and had a 21.7% higher specific capacity than that of a blank zinc electrode (419 mA h g−1 versus 344.3 mA h g−1) after 60 cycles. The ultrafine bismuth powder improved the nucleation efficiency, reduced the corrosion current, increased the polarization resistance threefold, and inhibited the formation of dendrites and corrosion, thereby increasing the battery specific capacity and cycle efficiency.

NANOSTRUCTURED EPOXY-BASED ANTICORROSIVE COATINGS

A functionalized epoxy resin (DGEBA) was synthesized from abietic acid, through the esterification and condensation reactions between the carboxyl groups of abietic acid and the basic functional groups of an epoxy resin. This method of synthesis increases the epoxy resin surface adhesion, as well as the chemical and thermal stability, for being used as a protective coating against corrosion of copper plates. Characterization analyses included FTIR and SEM of both raw and functionalized epoxy resin substrates performed. The corrosion performance of these coatings when applied onto Cu and stainless plates was tested in terms of: (i) immersion in a misty saline chamber, under accelerated corrosive conditions; (ii) Taber abrasion and (iii) hardness, adhesion and potentiodynamic polarization. The obtained results indicate the existence of a chemical bond between the epoxy ring and the carboxyl functional groups of abietic acid. This chemical bonding provided an increased adhesion as well as better chemical and thermal stabilities than those of the original resin. The corrosion resistance lining the functionalized epoxy resin films indicated that their anticorrosive efficiency was up to 30% higher than that of the functionalized resin.

Optimization of Espresso Spent Ground Coffee Waste Extract Preparation and the Influence of its Chemical Composition as an Eco-friendly Corrosion Inhibitor for Carbon Steel in Acid Medium

This work proposes the reuse of spent ground coffee waste (SCG) extracts as eco-friendly corrosion inhibitors for carbon steel in acid medium, and the correlation between their anticorrosive efficiency and chemical composition. The extraction method was optimized using a central composite design, and the chemical composition of the extracts was accessed using UV-Vis spectrometry, HPLC, and ICP-OES. EIS and Potentiodynamic Polarization (PP) tests evaluated the anticorrosive properties of the extracts. Total phenol content ranged from 93 mg L-1 to 219 mg L-1 Gallic Acid Equivalent. The highest concentration of phenolic compounds was observed for syringic acid (78.67 mg L-1), while the lowest concentration was verified for (-)-epigallocatechin-3-O-gallate (0.01 mg L-1). The Pearson correlation coefficient showed no correlation between the Rct and the total phenol content, although, positive correlations with the Rct was observed for caffeic acid, (+)-catechin, ferulic acid, and protocatechuic acid. EIS analysis revealed that all of the extracts could act as corrosion inhibitors. The best performance was verified for C3 extract (IE % = 94.83%). PP tests showed that this extract acted as a mixed inhibitor, with a predominant cathodic effect. Therefore, the valorization of the extracts as corrosion inhibitors was successfully achieved.

Biferrocenyl Schiff bases as efficient corrosion inhibitors for an aluminium alloy in HCl solution: a combined experimental and theoretical study.

The corrosion inhibitive capabilities of some ferrocene-based Schiff bases on aluminium alloy AA2219-T6 in acidic medium were investigated using Tafel polarization, electrochemical impedance spectroscopy (EIS), weight loss measurement, FT-IR spectroscopy and scanning electron microscopic (SEM) techniques. The influence of molecular configuration on the corrosion inhibition behavior has been explored by quantum chemical calculation. Ferrocenyl Schiff bases 4,4′-((((ethane-1,2-diylbis(oxy))bis(4,1-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene (Fcua), 4,4′-((((ethane-1,2-diylbis(oxy))bis(2-methoxy-1,4-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene (Fcub) and 4,4′-((((ethane-1,2-diylbis(oxy))bis(2-ethoxy-1,4-phenylene))bis(methaneylylidene))bis(azaneylylidene))bisferrocene (Fcuc) have been synthesized and characterized by FT-IR, 1H and 13C NMR spectroscopic studies. These compounds showed a substantial corrosion inhibition against aluminium alloy in 0.1 M of HCl at 298 K. Fcub and Fcuc showed better anticorrosion efficiency as compared with Fcua due to the electron donating methoxy and ethoxy group substitutions, respectively. Polarization curves also indicated that the studied biferrocenyl Schiff bases were mixed type anticorrosive materials. The inhibition of the aluminium alloy surface by biferrocenyl Schiff bases was evidenced through scanning electron microscopy (SEM) studies. Semi-empirical quantum mechanical studies revealed a correlation between corrosion inhibition efficiency and structural functionalities.

Luminescent coatings: White-color luminescence from a simple and single chromophore with high anticorrosion efficiency

Luminescent coatings have potential commercial applications. Here, the photoluminescence, thermal, and corrosion inhibition properties of reported Schiff bases have been studied. Moreover, quantum chemical calculations have been done to realize the working mechanism of their properties. Interestingly, we succeeded to get a single-chromophore white-color emission from a small Schiff base molecule through a simple technique, where the relative emission intensities at the long and short wavelengths of the visible range were controlled by introducing electron-donating or withdrawing groups. Furthermore, the compounds were found thermally stable and can emit efficiently until 124 °C. Also, the electrochemical impedance spectroscopy, electrochemical frequency modulation, Tafel polarization, and surface characterizations have been investigated. The studied compounds showed high inhibition efficiencies (ex. 93%) and played a great role in retarding the stainless-steel corrosion in 2 M H2SO4. These measurements confirmed that the existence of these Schiff bases can reduce the double-layer capacities, corrosion current densities, and corrosion rate simultaneously with increasing the charge transfer resistance values. The studied materials as luminescent coatings may be employed for mixed-type inhibitors and can provide a strategy for the development of new organic materials capable of producing white-color emission from a simple and single molecule.

Bioinspired Smart Anticorrosive Coatings with an Emergency-Response Closing Function.

Emergency-response closing (ERC) of diffusion pathways for aggressive species in graphene/epoxy (G/EP) coatings was achieved via terpyridine derivative (TDD)-functionalized graphene oxide (tGO). Under stimulation from corrosion produced ferrous (Fe2+) ions, tGO sheets urgently aggregated through complexation reminiscent of leaves closing on a mimosa. Consequently, the coating showed significantly decreased oxygen (ORT) and water vapor transmittance rate (WVTR) changes after immersion in ferrous solution. According to the simulation and electrochemical results, tGO sheets could self-assemble into 3D architectures with Fe2+ ions and efficiently protect metals from aggressive species attack. This tGO/EP coating provided an ERC function via self-adaptability with the Fe2+ ions to achieve long-term anticorrosion. The application of tGO/EP to the protection of metal components is therefore validated as a fascinating route for the enhancement of anticorrosion efficiency on graphene anticorrosive coatings, with great potential in durable anticorrosive coatings application.

Effective corrosion protection by eco-friendly self-healing PMMA-cerium oxide coatings

Metallic alloys are extensively used in many technological applications, however their susceptibility to corrosion causes huge economical losses and can result in failure of critical components. Aiming to obtain environmentally friendly, self-healing and high efficient anticorrosive coatings, organic-inorganic hybrids consisting of poly(methyl methacrylate) (PMMA) covalently bonded to CeO2/Ce2O3 nanoparticles have been synthetized by the sol–gel process. Cerium oxide nanoparticles were covalently conjugated with the coupling agent 2-hydroxyethyl methacrylate (HEMA) and different proportions of methyl methacrylate (MMA), and subsequently the hybrid solutions were used to deposit films on A1020 carbon steel by dip-coating. The coatings are transparent, homogeneous, free of pores, have low surface roughness (<1.6 nm), and present good thermal stability (>220 °C). Excellent anticorrosive efficiency and durability was obtained by the nanoscale dispersion of cerium oxide nanoparticles into PMMA matrix, achieving for the sample with molar ratio of 1Ce:2HEMA:25MMA an impedance modulus up to 290 GΩ cm2, 8 orders of magnitude higher than the bare carbon steel, remaining essentially unchanged during 6 months exposure to saline solution. A detailed analysis of scratched coatings evidenced that Ce ions act as self-healing agents inhibiting the progression of the corrosion process. This work demonstrates that the active corrosion inhibition and environmental compliance make these PMMA-cerium oxide coatings a very promising alternative for the conventional protection systems.

Sustainable corrosion inhibitor for steel in simulated concrete pore solution by maize gluten meal extract: Electrochemical and adsorption behavior studies

The corrosion inhibitive effect of maize gluten meal extracts for steel in simulated concrete pore solution with 3.0 wt% sodium chloride was investigated. The results acquired from EIS and polarization studies were in a good agreement, which suggest an increase in the corrosion resistance of steel with the extract introduced comparatively to the blank systems. Adsorption of extracts onto the steel surface obeyed the isothermal Langmuir adsorption, was mainly controlled by physisorption. The confirmatory evidence of enhanced corrosion resistance during adsorption was obtained from the SEM-EDS, ATR-FTIR and surface structure analysis. Furthermore, the amide bond structures of the main constituents in extract were also beneficial to adhere to steel surface. The sustainable extract of maize gluten meal is a by product of starch industry, which is an effectively and promisingly inhibitor for reinforced steel with the anticorrosion efficiency of 62.71–88.10%.

Anticorrosive efficiency of novel 1,4-benzothiazinone derivative for mild steel in phosphoric acid solution

Anticorrosive efficiency of novel 1,4-benzothiazinone derivative for mild steel in phosphoric acid solution

Graphene and Graphene/Polymer Composites as the Most Efficient Protective Coatings for Steel, Aluminum and Copper in Corrosive Media: A Review of Recent Studies.

The metal corrosion is considered as a severe threat to the national economy and industry structure, capable of triggering significant economic losses and severe damages, involving innumerable fields in daily life and industries. This review provides an overview of the physioelectrochemical studies on anticorrosive properties of various types of graphene coatings. Required electrochemical techniques for the investigation of anticorrosive efficiency, various types of graphene-based materials coatings along with different routes to provide desirable coated layers are discussed in detail. After all, we intend to show that the modified graphene nanosheets can be regarded as effective protective layers against metal corrosion not only because of their extraordinary mechanical strength and toughness, which can be reached with a vastly thin layer, but also for their high transparency, cost-efficiency and stability.

Preparation and properties of polymeric surfactants: A potential corrosion inhibitor of carbon steel in acidic medium

The polymeric surfactants were synthesized using allyl glycidyl ether, acrylamide, butyl acrylate and sodium allylsulfonate by radical polymerization and applied as corrosion inhibitor of carbon steel via weight loss method. The structure of polymeric surfactants was confirmed by FT-IR and NMR. The surface activity of polymeric surfactants was characterized by surface tension and wetting power. The anticorrosion mechanism of polymeric surfactants was confirmed by anticorrosion efficiency, the Gibbs adsorption free energy, SEM, AFM and XPS. The experimental results show that with the increase of the amount of polymeric surfactants, the corrosion resistance efficiency increases gradually, which proves that it is an effective corrosion inhibitor. The preparation process of the polymeric surface activity is simple which can be used for industrial production.

An Experimental and Theoretical Study of Biodegradable Gemini Surfactants and Surfactant/Carbon Nanotubes (CNTs) Mixtures as New Corrosion Inhibitor

Inhibition performance of noncovalent functionalization of carbon nanotubes (CNTs) with biodegradable gemini surfactants on mild steel surface in 2 M hydrochloric acid solution was examined by potentiodynamic polarization, electrochemical impedance spectroscopy and quantum chemical calculations. Ultraviolet–visible (UV–vis) spectroscopy, thermogravimetric analysis, Raman analysis, and zeta-potential (Z-potential) measurements are also applied to discuss the stability of studied solutions. Ester-containing cationic surfactants; monomeric betainate, dodecyl esterquat gemini (ET), and dodecyl betainate gemini (BT) were used as potentially superior noncovalent functionalization agents for CNT-based formulations. For the first time, the anticorrosive efficiency of these surfactants on mild steel was investigated. The noncovalent functionalization of CNTs with ester-containing surfactants showed more appropriate inhibition properties at higher surfactant concentrations as a result of further dispersing ability. The best inhibition efficiency (IEE = 93%) is reported for BT (2.5 mM)-suspended nanotubes, while the effectiveness is decreased (IEE = 12%) dramatically at low concentration (0.1 mM). Surface observations are also employed to verify the corrosion protection of mild steel covered with noncovalent functionalization of CNTs. Density functional theory was employed for quantum chemical calculations, and a good correlation between experimental data and theoretical data has been obtained.

A Powerful Nanocomposite Polymer Prepared From Metal Oxide Nanoparticles Synthesized via Brown Algae as Anti-corrosion and Anti-biofilm

The chemical/microbial bio-corrosion in water pipelines are the most common problem in industry worldwide which cause damage to expensive equipment and increases the maintenance costs. In this work, the green synthesis of nanocomposite was synthesized using brown algae (Sargassum muticum) extract. This method is eco-friendly and non-toxic. The synthesized nanocomposite was characterized using UV–vis spectroscopy, Dynamic light scattering (DLS), X-ray diffraction (XRD), Transmission electron microscopy (TEM) and FTIR analysis. The size of ZnO and CuO nanoparticles was reduced to 15nm and 20 nm respectively, after exposure to 60Co gamma-ray irradiation. The nanocomposite showed significant P-value (P<0.001) as a biofilm inhibitor and anti-adherence for Proteus mirabilis, Pseudomonas aeruginosa and Staphylococcus aureus, which were represented bio-corrosion index. The results of weight loss method showed that Proteus mirabilis caused the highest bio-corrosion rate (1.5 mpy) on mild steel coupon as examined by SEM. The nanocomposite prevented the adhesion of biofilm bacteria to carbon mild steel coupon which was confirmed by SEM examination. Finally, the nanocomposite showed highest anti-corrosion efficacy in 1M HCl at 150 ppm with high anti-corrosion efficiency (92.3%). The results of this study concludes that the green synthesized nanocomposite has multi-function to be used as anti-bacterial, anti-biofilm, anti-corrosion and anti-bio corrosion.

Practical adhesion measurements of protective coatings on bronze by three-point bending test

When attempting to sufficiently protect outdoor bronze monuments from corrosion, searches for an effective solution are usually based on coating applications which have a high anticorrosive efficiency. In order to correctly assess the level of protection provided by such coatings, adherence (practical adhesion) measurements need to be performed for the proper evaluation of the deterioration of coating systems with aging. Although a coupled study of adherence with aging would be of great interest, very few such studies are available. In this work, a methodological approach is proposed for the evaluation of coatings applied to metallic cultural heritage monuments of, based on the use of a three-point bending test. Adherence characterization of different protective coatings has been performed both on bare and on traditionally black-patinated bronze coupons (Cu–Sn alloy with 5.9 wt% Sn), which were used as basic model substrates. The investigated coatings were Incralac®, silane, sol–gel oxysilane, and a silane-modified polymethacrylate (an adhesion promoter for fluoropolymer). The results of measurements which were obtained before and after accelerated aging in concentrated acid rain made it possible to more easily differentiate between the various adherence levels of different coating systems. Coupled with adherence measurements, the results of systematic optical and SEM observation of the different failure morphologies are also presented. In the case of the coated bare alloy, adhesive failures were mainly observed. The silane (PropS-SH) coating showed the best adherence. In the case of the patinated bronze test specimens, only cohesive failures occurred. Adherence is directly related to the cohesion of the black patina rather than that of the applied coating. It was observed that aging reduces the level of the adherence.

Fabrication of durability superhydrophobic LDH coating on zinc sheet surface via NH4F-assisted in-situ growth and post-modification for enhancing anti-corrosion and anti-icing

In this work, a superhydrophobic layered double hydroxide (LDH) coating was fabricated on zinc sheet surface by in-situ growth and post-modification technology. The obtained zinc sheet exhibited excellent superhydrophobicity with a water contact angle (WCA) of 160° and a water sliding angle (WSA) of 5o. To determine the mechanical stability, chemical stability, storage stability of the superhydrophobic LDH coating on zinc surface, sandpaper abrasion test, tape-peeling test, immersion test and long-term exposure to the outdoors were employed. The results of stability test suggested that the LDH coating on zinc surface possessed excellent superhydrophobic stability (WCA > 150°, WSA < 10°) during all kinds of harsh conditions except pH = 1, indicating the superior adaptability to outdoor environment. More importantly, the superhydrophobic LDH coating on zinc surface exhibited excellent anti-corrosion efficiency (η = 99.99%) and delay icing ability (t = 75 min), which was beneficial to the application of zinc in a variety of practical fields.

Inhibitive effect of quaternary ammonium-type surfactants on the self-corrosion of the anode in alkaline aluminium-air battery

The most serious drawback of aluminium-air batteries with aqueous alkaline electrolytes is parasitical hydrogen evolution reaction. It is essential to identify an effective electrolyte additive for suppressing the self-corrosion of the aluminium anode. This work reports the inhibition effects of three quaternary ammonium-type surfactants, cetyl trimethyl ammonium bromide (CTAB), dihexadecyl dimethyl ammonium bromide (DDAB) and dodecyl dimethyl benzyl ammonium bromide (DDBAB), as corrosion inhibitors for the aluminium-air battery anode in 4 mol L−1 NaOH solution. Hydrogen collection technique, potentiodynamic polarization, electrochemical impedance and surface analysis are used to evaluate the corrosion inhibition properties of the additives. The results indicate that all the additives show anticorrosion efficiency in the order of DDBAB > CTAB > DDAB. The molecular structures of the surfactants are simulated by the density functional theory method in order to clarify the correlation between inhibition effect and the molecular structures. The presence of surfactants not only increases the voltage of the aluminium-air battery under galvanostatic discharge, but also increases the specific capacity markedly. Finally, the inhibition mechanism of cationic surfactants is proposed, and the reasons for the different inhibition performance of these additives are analysed.

Dispersion of Poly(urea-formaldehyde)-Based Microcapsules for Self-Healing and Anticorrosion Applications.

An effective dispersant, oleyl phosphate (OP), for the dispersion of poly(urea-formaldehyde)-based microcapsules in a typical epoxy coating material is proposed. Based on electron microscopy observations and rheological and mechanical characterizations, it is observed that the addition of merely 0.5 wt % of OP is sufficient to obtain good dispersion of the microcapsules in the epoxy. In the self-healing and anticorrosion experiments, a microcapsule content of at least 15 wt % is required to efficiently restore the epoxy matrix and provide corrosion protection to underlying low-carbon steel when the particles are not dispersed; however, the amount of microcapsules required to obtain good self-healing and anticorrosion efficiencies can be greatly reduced to only 5 wt % when the microcapsules are dispersed by OP.

Ircinia strobilina crude extract as corrosion inhibitor for mild steel in acid medium

The marine sponge Ircinia strobilina crude extract (ISCE) was analyzed as a corrosion inhibitor for mild steel in 1 mol L−1 HCl. The corrosion behavior was evaluated using weight loss method, potentiodynamic polarization, linear polarization resistance and electrochemical impedance spectroscopy. The results show an increase in anticorrosive efficiency as ISCE concentrations increase (from ±55% at 0.5 g L−1 to ± 82% at 2.0 g L−1). The surface was examined by diffuse reflectance infrared Fourier transform spectroscopy. The composition of the crude extract was chemically characterized by liquid chromatography-high resolution mass spectrometry. The protection mechanism was discussed.

Synthesis of thiophene derivatives and their anti-microbial, antioxidant, anticorrosion and anticancer activity

BackgroundA new series of thiophene analogues was synthesized and checked for their in vitro antibacterial, antifungal, antioxidant, anticorrosion and anticancer activities.ResultsA series of ethyl-2-(substituted benzylideneamino)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate derivatives were synthesized by using Gewald synthesis and their structures were confirmed by FTIR, MS and 1H-NMR. The synthesized compounds were further evaluated for their in vitro biological potentials i.e. antimicrobial activity against selected microbial species using tube dilution method, antiproliferative activity against human lung cancer cell line (A-549) by sulforhodamine B assay, antioxidant activity by using DPPH method and anticorrosion activity by gravimetric method.ConclusionAntimicrobial screening results showed that compound S1 was the most potent antibacterial agent against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhi having MIC value 0.81 µM/ml and compound S4 also displayed excellent antifungal activity against both Candida albicans and Aspergillus niger (MIC = 0.91 µM/ml) when compared with cefadroxil (antibacterial) and fluconazole (antifungal) as standard drug. The antioxidant screening results indicated that compound S4 and S6 exhibited excellent antioxidant activity with IC50 values 48.45 and 45.33 respectively when compared with the ascorbic acid as standard drug. Anticorrosion screening results indicated that compound S7 showed more anticorrosion efficiency (97.90%) with low corrosion rate. Results of anticancer screening indicated that compound S8 showed effective cytotoxic activity against human lung cancer cell line (A-549) at dose of 10−4 M when compared with adriamycin as standard.