Anticorrosion Applications Research Articles

A two-dimensional nanocontainer based on mesoporous polydopamine coated lamellar hydroxyapatite towards anticorrosion reinforcement of waterborne epoxy coatings

Two-dimensional (2D) nanocontainers provide exciting opportunities in anticorrosion application through a skillful combination of delivery functionality for corrosion inhibitors and barrier property of lamellar materials. Herein, we used a versatile emulsion-induced approach to synthesis sandwich-like 2D nanocontainers based on mesoporous polydopamine (PDA) heterostructures on ultrathin bio-ceramic hydroxyapatite (HA) nanosheets. Triblock copolymer and 1,3,5-trimethyl benzene (TMB) synergistically promote the formation of well-defined mesoporous structure. The porous PDA not only provides large amount of contact interface for embedding benzotriazole (BTA), but also serves as another important corrosion inhibitor to achieve active protection effect. In addition, rich functional groups in PDA structure ensure the fine interface compatibility between lamellar HA and waterborne resin, leading to the improvement in terms of coating barrier performance. In comparative evaluation, the composite coatings containing BTA-loaded nanocontainers (1 wt%) exhibit high impedance value (Zf=0.01 Hz) in 3.5 wt% NaCl solutions for 60 days, indicating the long-term anticorrosion properties. Meanwhile, local electrochemical impedance technology proves nanocontainers with BTA loaded obviously inhibited the corrosion reactivity in corrosive microregions. This work puts new insights into designing functional anticorrosion coatings based on the surface construction on 2D materials, which has potential application for improving coating service life in marine environment.

Nano-SiO2 and Silane Coupling Agent Co-Decorated Graphene Oxides with Enhanced Anti-Corrosion Performance of Epoxy Composite Coatings.

Coatings are of great significance for irons and steels in regards to the harsh marine environment. Graphene oxides (GO) have been considered as an ideal filler material of epoxy coating. However, the undesired dispersion in the epoxy together with easy agglomeration and stacking remain great problems for practical application of GO composited epoxy coatings. A method that can effectively solve both self-aggregation and poor dispersion of GO is highly desired. Herein, we present a high dispersion strategy of graphene oxides in epoxy by co-decoration of nano-SiO2 and silane coupling agent. The co-decorated GO filled epoxy coating exhibits high anti-corrosion performance, including high electrochemical impedance, high self-corrosive potential, low self-corrosive current, and superior electrochemical impedance stability for ten days to Q235 carbon steel. This work displays new possibilities for designing novel coating materials with high performance toward practical marine anti-corrosion applications.

Versatile reactions on hydrophobic functionalization of metal-organic frameworks and anticorrosion application

Four post-synthetic modification (PSM) reactions to incorporate alkyl chains onto metal-organic frameworks (MOFs) were explored by using various organic transformation reactions. The modified hydrophobic MOFs can reduce the interface voids within the MOF-polymer composites. In this work, it was demonstrated that the decorated hydrophobic MOFs eliminated the interfacial voids in the MOF-polyaniline (PANI) composites and increased the anticorrosion performance. In particular, PAZr-C18-5% composite exhibited significant anticorrosive properties as the corrosion current density was reduced from 71.61 to 0.18 μA/cm2. Furthermore, the doping of hydrophobic MOFs into PANI can also increases the composite's surface hydrophobicity and improve its gas barrier performance.

Multifunctional silver nanocomposite: A potential material for antiscaling, antimicrobial and anticorrosive applications

Present investigation aims for the synthesis and characterization of a new eco-environmental and cost-effective silver nanocomposite (AgNPs) for application as multifunctional inhibitor of scaling and corrosion. The AgNPs was synthesized by reduction of silver ions using Allium cepa peels extract. The AgNPs exhibit impressive stability and resistance to thermal and biochemical degradation. The AgNPs were round shaped, monodispersed and non-aggregated, with surfaces rich in oxygen and nitrogen sites. Compared to the crude extract, AgNPs exhibits higher antimicrobial activity and afforded a 3-log reduction in population of Desulfovibrio sp. At 30 ​°C, AgNPs inhibits carbonate scale, sea water corrosion and bio-corrosion at efficiencies of 30.8%, 14.4% and 55.9%, respectively, and 37.4%, 37.3%, 45.6%, respectively at 60 ​°C. AgNPs sustained its high efficiency even after being preserved for 180 days and addition of d -tryosine and mevalonic acid phosphate further intensified the efficiency by synergistic effect. • Biogenic silver nanoparticles (AgNPs) inhibits calcium scales and corrosion in microbial and sea water environments. • AgNPs very stable to thermal and biochemical degradation. • AgNPs very efficient and effective over 180 day’s storage. • D-tryosine and mevalonic acid phosphate synergistically potentiate efficiency of AgNPs.

Adaptability of sol-gel anti-corrosion coating on different metallic substrates

In this paper, the adaptability of sol-gel anti-corrosion coating applied in space station on different metal substrates, such as aluminium, titanium, steel and copper, has been analysed, and anti-corrosion performances of the sol-gel coating have been evaluated here. The electro-chemical properties of the coating on different substrates are tested by potentiodynamic polarization curves and AC impedance spectroscopy. The results show that the anticorrosive effect of the sol-gel coating on titanium, steel and copper substrate is obviously better than that of aluminium alloy. For different designations of aluminium alloy, the anti-corrosion effect of 2A12 Al alloy is better than that of 5A06 Al alloy, which may be related to the metal composition in the substrate. The corrosion resistance of 2A12 containing Cu is better than that of 5A06 series containing Mg. This study will provide references for the application of sol-gel anticorrosion coating and surface anticorrosion of aerospace products.

Coat multi-layered graphene on Cu with radiofrequency plasmas for anti-oxidization in hot air

Direct and fast synthesis of protective coating on metal surfaces is a major challenge in anti-corrosion applications of 2D graphene. In this article, we provided an approach to this challenge by using radiofrequency plasmas, where the mixture of CH4/H2 or pure CH4 gases can be decomposed under low temperature while the temperature of the Cu foil substrates can still be kept high by the induced eddy current. The high substrate temperature is essential for enhancing graphene quality, but many other plasma synthesis techniques seldom addressed this point. Graphene coatings with thicknesses of about 30 nm could be obtained in 3.5 min. Anti-corrosion tests examine protection coatings under various conditions. In this article, we mainly checked the protection performance of the graphene coatings against Cu oxidization in air. Anti-oxidization tests under 300 °C for 360 min proved that the coatings synthesized with pure CH4 performed better over those synthesized with mixture of CH4/H2. Tests under 200 °C for 900 min and 22 °C for 111 days demonstrated that the coatings synthesized with different gas compositions had equivalent anti-oxidization capabilities. Our calculations with density functional theory revealed that the defective single-layered graphene was unable to protect the Cu substrate, and it would be better to use multi-layered graphene in practice. The synthesis technique in this article could also be used in many other areas beyond anti-oxidization such as chemical reaction catalysis, electrode materials, electromagnetic interference shielding and so on.

New valve-free organosilica nanocontainer for active anticorrosion of polymer coatings

Smart coatings with inhibitor loaded nanocontainers exhibit significant efficiency and durability in prolonging metal life-time and reducing catastrophic failure. However, scaling and further practical intelligent anticorrosion applications of such coatings are still greatly limited by time-consuming installation of various nanovalves. Herein, hybrid hollow mesoporous organosilica was obtained by facile selective etching and served as valve-free nanocontainer to prepare smart anticorrosive coatings. Intelligent functions for inhibitor release and coating active corrosion protection are executed by the cargo-framework interaction, which is sufficiently demonstrated by experimental and computational results. Specifically, inhibitor is encapsulated at neutral pH and released under acidic conditions, which can make nanocontainer spontaneously undergo the pH changes resulted from coating damage and corrosion onset, then respond quickly to achieve in situ repair of corrosion. Correspondingly, exposure of the coating sample containing loaded nanocontainer in NaCl solution shows negligible corrosion and exhibits an increase of Rc (from 606.1 kΩ cm2 to 2967 kΩ cm2) and Rct (from 244.1 kΩ cm2 to 1985.5 kΩ cm2) with the immersion time, while significant deterioration of controlled samples (Rct from 118.7 kΩ cm2 to 46.9 kΩ cm2 and from 5.22 kΩ cm2 to 1.93 kΩ cm2, respectively). Notably, this nature-gated approach will provide novel idea for the preparation of smart nano delivery system for smart anticorrosive coatings.

Lignin from termite frass: a sustainable source for anticorrosive applications

The present study reports a sustainable source of lignin, from termite frass. Lignin was extracted using Klason’s method and subjected to polarization studies to check the inhibition efficiency and measured the electrochemical performance of the coated sample on the carbon steel using electrochemical impedance spectroscopy. The anticorrosive property was determined in a simulated corrosive environment (0.1 M NaOH and 0.5 M NaOH). The morphological analysis of the surface of both bare metal and the lignin-coated ones, before and after exposure to the corrosive environment, was recorded using atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy-dispersive X-Ray spectroscopy (EDX). The lignin showed maximum inhibition efficiency at 600 ppm in 0.5 M NaOH solution. Moreover, the lignin coated on carbon steel exhibited about 70% corrosion inhibition efficiency as recorded by potentiodynamic polarization studies and electrochemical impedance spectroscopy. The AFM and SEM analyses further corroborated the protection of the metal surface from corrosion when coated with lignin. Hence, the study suggests lignin from termite frass as a sustainable biological source suitable for anticorrosive applications.Graphic abstract

Designing a Highly Stable Slippery Organogel on Q235 Carbon Steel for Inhibiting Microbiologically Influenced Corrosion.

Microbiologically influenced corrosion (MIC) accelerates the corrosion and degradation of metal materials due to the settlement of microorganisms on the surface. However, environmentally friendly and efficient methods to fabricate antifouling and anticorrosion surfaces are still lacking. Inspired by Nepenthes, a slippery liquid-infused porous surface (SLIPS) has been proven to be an efficient way to inhibit settlement of microorganisms on the metal surface and the following MIC due to the existence of a mobile defect-free lubricant layer. However, the stability of the lubricant layer and substrate of the SLIPS prevented its long-term antifouling and anticorrosion application. Herein, a highly stable slippery organogel was fabricated by depositing a homogeneous mixture of PDMS (base and curing agent), silicone oil, triethoxyvinylsilane, and SiO2 on Q235 and curing in an oven. Triethoxyvinylsilane was not only able to cross-link with the curing agent of PDMS through hydrosilylation but also able to interlink the organogel and Q235 through condensation between the -OH of the metal surface and hydrolyzed siloxane. As a result, the adhesion force between the organogel without triethoxyvinylsilane and the substrate (0.45 MPa) increased to 1.50 MPa for the organogel with triethoxyvinylsilane and SiO2. Also, the tensile strength of the organogel without SiO2 (0.97 MPa) increased to 3.88 MPa for the organogel with 2 wt % SiO2 because of the high elastic modulus of SiO2, which was important to improving its stability under external force. In addition, the organogel showed stable oil distribution and slippery performance after spinning at 4000 rpm for 30 s. Then, the bacterial settlement demonstrated that the organogel could effectively inhibit Pseudoalteromonas sp. settlement on the substrate under both static and dynamic conditions. Finally, an electrochemical test indicated that the MIC could be effectively mitigated by the organogel. This study provides an efficient method to fabricate a highly stable slippery surface on a metal surface for its potential application in mitigating MIC.

Polydopamine improved anticorrosion of graphene on copper: Inhibiting galvanic corrosion and healing structure defects

Galvanic reaction and structure defect remained as two longstanding challenges seriously limit the anticorrosion application of graphene (GR). To improve anticorrosion performance of graphene as protect barrier for metals, in the present study, polydopamine (pDA)-graphene (pDA-GR) composites were synthesized on Cu substrate, manifesting pDA-wrapped-GR microstructural features. The experimental results indicated the defects intrinsically located in GR could be healed by pDA via π-π interaction, resulting in effectively improved corrosion resistance. The protection coefficient of pDA-GR is increased to 99.8%, higher than pristine GR. The mechanism concerning both better impermeability of few-defect-graphene and non-conductivity of pDA layer was proposed to inhibit the galvanic coupling reaction between GR and metal substrate. The compositing strategy provided herein may path a new way to improve the anticorrosion performance of GR.

The fabrication and anticorrosive performances of sulfonate‑barium@sulfonated graphene composite filler

Graphene material has been used as a superior protection barrier for metal surface due to its excellent impermeability to corrosive electrolyte. However, it is not satisfactory for long-term corrosion resistance of graphene, which has a tendency to agglomerate in the resin coating. In this study, a novel anticorrosion filler was fabricated by sulfonated graphene (GS) sheets wrapping sulfonate‑barium (BS) nanoparticles. The composite material (BS@GS) exhibited a flake-like structure with numerous BS nanoparticles (particle size of 20–50 nm) on the sheet surface. The introduction of BS@GS filler in epoxy resin coating could significantly enhance corrosion resistance of carbon steel. For instance, when added only 4 wt% of BS@GS filler, the impedance modulus at 0.01 Hz of composite coating was still maintained as 1.576 × 105 Ω cm2 after immersion in NaCl solution for 168 h, about 2 orders of magnitude higher than pristine resin coating. It demonstrated that this work developed an effective strategy to achieve long-term anticorrosion application for the graphene material.

Mussel-inspired facile fabrication of dense hexagonal boron nitride nanosheet-based coatings for anticorrosion and antifriction applications

Although great progress has been made recently in the research of hexagonal boron nitride (h-BN) nanosheets, their practical applications are limited due to the difficulties of processability. Existing methods to modify h-BN usually suffer from tedious steps and chemical oxidation reaction conditions, which are being phased out owing to human health and environmental concerns. Herein, inspired by the mussel, dopamine is selected to functionalize h-BN (polydopamine-functionalized hexagonal boron nitride [h-BN@PDA]) nanosheets which can improve interfacial compatibility thus enhancing their processability. As expected, dense h-BN@PDA nanosheet-based coatings can be fabricated through a facile environmentally friendly spraying process in the assistance of polyvinyl alcohol (PVA). The as-obtained coatings present excellent thermal stability because of the hydrogen bonds formed between h-BN@PDA and PVA. Additionally, suitable PVA is beneficial for load transfer, thus improving the mechanical properties of the coatings. More importantly, the composite coatings show good anticorrosion and antifriction performance since the h-BN@PDA nanosheets can act as physical barrier to corrosive medium and oxygen, or be stored in the worn surface as lubricant to reduce the friction and strengthen the friction stability. The facile fabrication process combined with the good thermal stability, anticorrosion and antifriction properties makes the h-BN@PDA nanosheet-based coatings promising candidates for practical applications.

Recent advances in steel surface treatment via novel/green conversion coatings for anti-corrosion applications: a review study

Recent advances in steel surface treatment via novel/green conversion coatings for anti-corrosion applications: a review study

The use of FCNT/PANI nanocomposites to extend the life of lithium-ion batteries

Abstract The contact between aluminum foil (current collector) and LiTFSI salt electrolyte not only causes surface corrosion problems but also decreases the shelf life of the lithium-ion battery (LIB). In this work, we develop new composites coatings that are able to protect the aluminum foil from corrosion in the LIB. The new composites contain functionalized carbon nanotubes and polyaniline conductive polymer (FCNT/PANI). The performance of new composites is evaluated using various experiments including cyclic voltammetry (CV) and chronoamperometry (CA). The charge and discharge cycles of the LIB cell with scanning electron microscopy (SEM) are used to investigate the battery performance and the morphology of the aluminum foil. Towards anti-corrosion application, FCNT/PANI composites can successfully suppress the pitting corrosion of Al foil in 1.0 M LiTFSI electrolyte. The FCNT/PANI composite that uses 1.0% FCNT shows a superior rate capability and anti-corrosion performance when compared with composites that use the 0.2 and 0.5% FCNT. Further, the lithium-ion battery with coated Al foils with FCNT/PANI composites gives an excellent cyclability. Overall, these results confirm that the FCNT/PANI composites are a determining factor for lithium-ion battery efficiency.

Hybrid siloxane-epoxy coating reinforced by worm-like graphene oxide with improved mechanical properties and corrosion resistance

Graphene-based hybrid coatings have received considerable research interest in realizing the anti-corrosion application due to their high strength and impermeability. Graphene morphology is an important factor in determining the behaviors of composites. However, there have been few reports on the application of GO nanoscrolls in anti-corrosion coatings. Here, we obtained a hybrid siloxane-epoxy (SE) coating reinforced with worm-like graphene oxide (FGO) nanoscrolls for the protection of AA2024 alloy. GO sheets were firstly functionalized with tetraethoxysilane (TEOS) through a sol–gel method and incorporated into the SE resin via a wet transfer method. Chemical, structure and morphological analyses revealed that FGO sheets with active -Si-OH groups, increased surface wrinkles and decreased layers were obtained. During the transfer process, Si-OH guided the transformation of FGO into the tubular structure. Ultrasonication provided the required activation for scrolling and the vacuum cavity offered the deformation space. FGO sheets resulted in better dispersion and interfacial interaction. The positive effect of the characteristic structure on the mechanical and anti-corrosion properties of the coating outweighed the negative effect of the laminated stacking GO. SE/FGO coatings were characterized by high cross-linking density, toughness, flexibility, easy-produced and eco-friendly. This work provides a new strategy for developing high-performance graphene-based nano coatings.

L-Alanine methyl ester nitrate ionic liquid: synthesis, characterization and anti-corrosive application

The inhibition effect of amino acid-based ionic liquid (IL), L-Alanine methyl ester nitrate referred to as L-AlaC1NO3 IL on the corrosion of mild steel (MS) in 1 M HCl was investigated by weight loss and electrochemical measurements at temperatures ranging from 30 °C to 60 °C. The percentage inhibition effieicency increased with the increase of the concentration of the inhibitor and reached about 66.1% at the concentration of 0.003 M at 30 °C. On the other hand, the percentage inhibition increased with the increase of temperature and reached 84.0% at 60 °C on the same inhibitor concentration. Furthermore, the contact angle measurement and surface studies revealed water-repelling property and the protecting capability of the investigated inhibitor. The electronic property of L-AlaC1NO3 IL has been explored using density functional theory (DFT) and the sites susceptible for electron sharing were identified through Fukui indices analysis. Additionally, the Monte Carlo approach in molecular dynamics simulation evidenced the spontaneity of inhibitor’s interaction onto MS surface through donor–acceptor interactions leading towards flat-lying adsorption orientation.

Corrosion Behavior of Ni–Fe–Mo Deposits Obtained under Different Electrodeposition Conditions

Ternary Ni–Fe–Mo coatings have been proposed for anti-corrosion applications to replace chromium coating. To analyze the effects of deposition current and duration six different Ni–Fe–Mo films have been electrodeposited on copper foils. Their morphologies, structures, and chemical compositions of the films have been characterized. Potentiodynamic polarization is applied on each coating and electrochemical impedance spectroscopy is applied to discuss their corrosion resistances. Ni–Fe–Mo film that is produced at the lowest current density (5 mA.cm-2) for 5 min. exhibits a more positive corrosion potential and higher charge transfer resistance. To shed some lights on aging mechanism, the film has been aged for 70 days. The enhanced protective properties of the film is attributed to its fine, crack free morphology with high Mo content. The existences of Fe2O3, MoO2, MoO3, and NiO in the passive layer substantiate the improved barrier protection ability of the film.

In situ assemble Ti3C2Tx MXene@MgAl-LDH heterostructure towards anticorrosion and antiwear application

Despite two-dimensional Ti3C2Tx MXene as a promising candidate in enhancing the anticorrosion and antiwear abilities of epoxy coating, its natural restacking tendency seriously impedes the real-world application of Ti3C2Tx/epoxy composite coating. Hence, Ti3C2Tx MXene@MgAl-LDH heterostructure composites are obtained by in situ assembly through electrostatic interaction. The interaction between Ti3C2Tx MXene and MgAl-LDH is investigated by first-principles calculations based on density functional theory (DFT), confirming Ti3C2Tx MXene@MgAl-LDH heterostructure with favorable binding stability. More importantly, Ti3C2Tx MXene@MgAl-LDH achieves excellent dispersibility and compatibility with epoxy resin. As-prepared Ti3C2Tx MXene@MgAl-LDH/epoxy coating (C-MXene@LDH) exhibits satisfactory corrosion/wear protection and certain self-healing performance, owing to the synergy of good dispersibility, barrier effect and the corrosion inhibitor release of Ti3C2Tx MXene@MgAl-LDH. This work is of great significance for MXene-based heterostructure composites to take a giant step forward in anticorrosion and antiwear application.

MgAl-V2O74- LDHs/(PEI/MXene)10 composite film for magnesium alloy corrosion protection

In this study, MgAl-V2O74- LDHs/(poly(ethyleneimine)(PEI)/MXene)n composite films were synthesized via (i) in-situ hydrothermal growth of Mg-Al layered double hydroxides (LDHs) on AZ31 alloy followed by vanadate intercalation reactions, and (ii) the as-prepared MgAl-V2O74- LDHs film was covered by layer-by-layer assembly using (PEI/MXene)n, where n=5, 10, and 20. Film characterization revealed that the outer layers (PEI/MXene) were assembled on the surface by electrostatic interaction and provided a good coverage of LDHs nanosheets. But, microcracks appeared gradually on the surface and destroyed the film integrity with increasing number of PEI/MXene layers. The corrosion tests indicated that the MgAl-V2O74- LDHs/(PEI/MXene)10 composite films provided a better corrosion protection ability than that of n=5 and 20. The outer layers (PEI/MXene) had a corrosion inhibition protective effect on MgAl-V2O74- LDHs film. This work opened a new perspective of the MXene materials for anticorrosion application via a layer-by-layer assembly method.

Thermal Atomic Layer Deposition of Yttrium Oxide Films and Their Properties in Anticorrosion and Water Repellent Coating Applications

The thermal atomic layer deposition (ThALD) of yttrium oxide (Y2O3) was developed using the newly designed, liquid precursor, Y(EtCp)2(iPr2-amd), as the yttrium source in combination with different oxygen sources, such as ozone, water and even molecular oxygen. Saturation was observed for the growth of the Y2O3 films within an ALD window of 300 to 450 °C and a growth per cycle (GPC) up to 1.1 Å. The resulting Y2O3 films possess a smooth and crystalline structure, while avoiding any carbon and nitrogen contamination, as observed by X-ray photoelectron spectroscopy (XPS). The films showed strong resistance to fluorine-containing plasma, outperforming other resistant materials, such as silicon oxide, silicon nitride and alumina. Interestingly, the hydrophilic character exhibited by the film could be switched to hydrophobic after exposure to air, with water contact angles exceeding 90°. After annealing under N2 flow at 600 °C for 4 min, the hydrophobicity was lost, but proved recoverable after prolonged air exposure or intentional hydrocarbon exposure. The origin of these changes in hydrophobicity was examined.