Superior Anticorrosion Research Articles

Robust Anticorrosive Polymer Thin Film for Reliable Protection of Ingestible Devices.

Ingestible devices (ID) provide a safe and noninvasive method for monitoring, diagnosing, and delivering drugs to specific sites in the human body, particularly within the gastrointestinal (GI) tract. However, the GI environment is highly acidic and humid, which can cause IDs to fail, and their corrosion in the acidic environment can cause leaching of toxic metal ions, thereby substantially limiting their long-term use. Thus, an efficient method is required to protect IDs, especially in the chemically and mechanically harsh GI environment. However, an anticorrosive polymer coating that can safeguard IDs in the GI environment without delamination or performance degradation has not been developed to date. The protective layer must satisfy several critical requirements, e.g., high biocompatibility, mechanical durability, and superior anticorrosion performance. This paper reports a highly cross-linked but submicron-thick siloxane-based anticorrosive polymer thin film that can be deposited directly onto IDs without damaging them. The 500 nm-thick cross-linked polymer coating demonstrates exceptional corrosion resistance and chemical and mechanical stability in the GI environment without cytotoxicity. A printed circuit board (PCB) coated with the developed ultrathin protective film sustained performance after exposure to a pH 1.00 phosphate buffered saline solution at 37 °C for 72 h without leaching of metal ions. The ID continued to operate effectively under such challenging conditions; thus, the developed film is suitable for applications that require prolonged functionality, e.g., diagnostics, drug delivery, and continuous health monitoring in the GI tract.

Cooperative Use of N-Heterocyclic Carbenes and Thiols on a Silver Surface: A Synergetic Approach to Surface Modification.

Surface modification through the formation of a self-assembled monolayer (SAM) can effectively engineer the physicochemical properties of the surface/material. However, the precise design of multifunctional SAMs at the molecular level is still a major challenge. Here, we jointly use N-heterocyclic carbenes (NHCs) and thiols to form multifunctional hetero-SAM systems that demonstrate excellent chemical stability, electrical conductivity, and, in silico, catalytic activity. This synergistic effect is facilitated by the high surface mobility and electron-rich nature of NHCs, combined with the strong binding strength of thiols. Scanning tunneling microscopy, electrical conductivity, and scanning electron microscope measurements, as well as density functional theory calculations, were employed to explore the synergistic interactions in the supramolecular SAMs. The van der Waals integration of ballbot-type NHCs and thiols enables the SAMs to exhibit both superior surface anticorrosion properties (attributing to the shift in the d-band center) and low surface resistance originating from the band alignment. Moreover, we find that the deposition sequence of flat-lying NHCs and thiols results in SAMs with different configurations, which can further tune the mechanistic pathway in silico in the acetylene hydrogenation process. Our results provide essential molecular insights into the local electronic control of the new SAM/metal interface and the high stability of the emergent multifunctionality (NHC/thiol)-SAMs forming self-assembled lamellae structures in the nanometer regime.

Dual-oxides confined carbonyl iron enabling superior electromagnetic wave absorption and anticorrosion performance

With the increasing requirements of electromagnetic wave (EMW) absorption, developing EMW absorbers with high-efficiency anti-corrosion performance which can be effectively applied in extreme corrosive environments is imperative and constitutes a hot issue in the current research. Herein, based on the composition modulation of ZrO2 and SiO2 layer, the dual-oxides confined carbonyl iron (CI@ZrO2/SiO2) composite displays a minimum reflection loss (RLmin) of −48.58 ​dB@1.9 ​mm and an effective absorption bandwidth (EAB) of 7.62 ​GHz@1.6 ​mm. Besides, the CI@ZrO2/SiO2 displays superior corrosion resistance with corrosion current density (icorr) of 8.62 ​× ​10−7 A/cm2 and polarization resistance (Rp) of 3.64×105 ​Ω. This work proposes a strategy to optimize the broadband EMW absorption properties as well as the mass production toward the corrosion resistance applications.

An Imine-Functionalized Silicone-Based Epoxy Coating with Stable Adhesion and Controllable Degradation for Enhanced Marine Antifouling and Anticorrosion Properties.

Biofouling and corrosion of submerged equipment caused by marine organisms severely restrict the rapid development of the marine industry. Traditional antifouling or anticorrosion coatings typically serve a sole purpose and exhibit limited degradability upon failure, rendering them inadequate for current demands. Herein, a novel imine-functionalized command-degradable bio-based epoxy coating (SAHPEP-DDM) with enhanced integrated antifouling and anticorrosion performances was synthesized utilizing 1,3-bis (3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and syringaldehyde. Compared with commercial epoxy resins (E51-DDM) and polydimethylsiloxanes (PDMS), the SAHPEP-DDM coating exhibits superior antifouling and anticorrosion properties due to the existence of -C=N- and Si-O-Si chain segments in the cross-linking network. The coating achieves resistance rates of 99.59 % and 99.20 % against E. coli and S. aureus, respectively, and shows promising resistance against algae and proteins, as well as excellent corrosion resistance in artificial seawater (with |Z|0.01 Hz and arc radius of about 1011 Ω and exceeding 1010 Ω respectively). The coating also exhibits excellent chemical resistance in organic solvents as well as neutral and alkaline environments. Moreover, its controlled degradation after coating failure can be achieved in acid aqueous solutions through temperature and acidity adjustments, facilitated by the presence of -C=N-. This work presents a novel degradable coating successfully coupled the dual functions of antifouling and anticorrosion coatings, avoiding the employment of intermediate coat, indicating vast potential for application in various marine engineering fields.

Development and characterization of corrosion-resistant plasma-sprayed Ni-Al composite coatings via graphene oxide fillers

In this study, the authors propose a procedure to enhance pure Ni-Al powders through graphene oxide dispersion in water for plasma spraying. The enhanced powders were utilized to coat A36 steel via plasma spraying. Next, the powders and the coatings were characterized by energy-dispersive X-ray spectroscopy, X-ray diffraction analysis, micro-Raman spectroscopy, and field emission scanning electron microscopy. Given the capability of the generated X-ray to characterize near surfaces to a depth of a few micrometers, the performed X-ray microanalyses convey that the carbon species incorporated within the powders through the graphene oxide dispersion can act as nanofillers reducing the number of holes/pores in the plasma-sprayed coatings. Potentiodynamic polarization testing and electrochemical impedance spectroscopy were used to investigate the corrosion behavior of the samples at two intervals: after 1 h and after 30 days of exposure to a 3.5 % NaCl solution. According to the results of the corrosion testing, the enhanced coatings can display about 2.35 times lower corrosion current density compared to pure Ni-Al coatings, with the corrosion potentials of the enhanced coatings being higher than that of pure Ni-Al coatings (i.e., improved corrosion resistance). This improvement in corrosion resistance is also evident when the enhanced coatings are compared to the A36 substrate after 30 days of exposure to the solution. It appears that the incorporated carbon nanofillers, by reducing deep holes and pores that communicate with the surface of the substrate, ultimately determine the highest corrosion resistance. Thus, the outcome offers enhanced Ni-Al coatings possessing superior anticorrosion properties that typical plasma-sprayed Ni-Al bond coats may not exhibit.

Step-by-Step Tuning of Tribological and Anticorrosion Performance of Zinc Phosphate Conversion Coatings through Effective Integration of Spherical P-Doped MoS2 Nanoparticles.

Surface coatings with enhanced mechanical stability, improved tribological performance, and superior anticorrosion performance find immense application in various industrial sectors. Herein, we report the development of multifunctional composite zinc phosphate coatings by the effective integration of a structurally and morphologically tuned P-doped MoS2 nanoparticle additive (3P-MoS2) into the zinc phosphate matrix to offer attractive characteristics suitable for industrial applications. The integration of spherical nanoparticles as additive leads to the formation of homogeneous and compact coatings with a densely packed crystalline microstructure having enhanced microhardness, distinctive leaf-like morphology, and comparatively smooth topographical features. The attractive lubricity of the additive (3P-MoS2), coupled with its spherical morphology, facilitates a transition from sliding to rolling friction and contributes significantly toward the performance enhancement of the tuned composition of the composite zinc phosphate coating (0.3-PMS). Thus, the tuned 0.3-PMS coating delivers the lowest specific wear rate (1.334 × 10-5 mm3/Nm) and coefficient of friction (0.114) that significantly outperform bare-zinc phosphate coating. Further, the electrochemical corrosion study results indicate the improvement in corrosion resistance behavior of the composite zinc phosphate coatings with reduced corrosion current density (icorr) and charge transfer resistance (Rct) values, as compared to the bare-zinc phosphate coating. The effect of passivation in conjunction with the barrier protection characteristics of the composite coatings induced by the optimal composition of the integrated additive nanoparticles (3P-MoS2) can efficiently prevent the infiltration of corrosive ions and thereby significantly reduce the rate of corrosion.

A self-healing MoS2/GO hybrid polyurethane-based coating with superior anticorrosion performance for Q235 steel

The application of conventional organic coatings as a method of surface protection for carbon steel materials is a widely adopted practice. Nevertheless, the protective capacity of the coating is limited by the occurrence of defects during the curing process and the rapid intrusion of acidic media. In this work, a self-healing anti-corrosion hybrid coating, designated as MoS2-APTES-GO-PU, has been successfully fabricated on Q235 steel, which exhibits excellent protection in acidic oil well formation water. Molybdenum disulfide (MoS2) is grafted onto the surface of graphene oxide (GO), through a facile 3-aminopropyltriethoxysilane (APTES) hydrolysis method to forming a highly cross-linked three-dimensional network structure, which is homogeneously dispersed in self-healing polyurethane (PU). The incorporation of GO has been found to result in a labyrinth effect, which can be attributed to the extensive specific surface area. Furthermore, the uniform distribution of MoS2 on the surface can remarkably improve the anticorrosion properties. This phenomenon can be ascribed to the MoS2 effectively limiting the rapid galvanic corrosion between GO and substrates in acidic corrosive media. MoS2-APTES-GO rectifies the phenomenon that APTES-GO depletes the dynamic hydrogen bonding groups in PU due to the abundance of active groups on the surface, thereby improving the self-healing ability of the coating. Additionally, the MoS2-APTES-GO maintains a stable chemical structure when subjected to acidic conditions own to the excellent chemical stability of GO and MoS2, which can effectively delay the rapid penetration of corrosive media. Based on the electrochemical tests, the corrosion current density of 0.4 wt% MoS2-APTES-GO-PU coating is reduced to 7.35 × 10−11 A/cm2 from 1.03 × 10−8 A/cm2 of pure PU coating and the self-healing efficiency reaches 1.98 × 107 Ω cm2/h. The current 0.4 wt% MoS2-APTES-GO-PU coating is self-healing and has favorable corrosion resistance for application in acidic environment.

Silane functionalization of titania-graphene oxide nanocomposite for superior anticorrosion polyurethane coatings on steel

This research investigated the enhancement of anti-corrosion properties in polyurethane (PU) coatings on steel substrates through the Silane (N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane) functionalization of Graphene Oxide (GO) with Titania (TiO₂) nanoparticles. Comprehensive characterization techniques, including Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), Thermogravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray diffraction analysis (XRD), Brunauer-Emmett-Teller (BET), and electrochemical analyses, confirmed the effective integration of TiO₂ within GO layers. The SEM and TEM analyses showed uniform dispersion of TiO₂ nanoparticles, while TGA indicated improved thermal stability of the functionalized GO-TiO2 (fGO). FTIR and XRD analyses verified the composite's successful chemical bonding and structural integrity. BET analysis revealed a specific surface area and pore volume reduction from 505.540 m²/g and 0.867 cc/g for GO to 211.622 m²/g and 0.708 cc/g for fGO, respectively. The enhancement in anti-corrosion properties can be attributed to the uniform dispersion of TiO₂ nanoparticles within the GO matrix, which increases the coating's barrier properties by filling pores and voids. This prevents electrolyte penetration and enhances adhesion to the steel substrate, inhibiting corrosion. Electrochemical analysis demonstrated excellent corrosion resistance of fGO-modified PU coatings, with a maximum observed resistance of 0.821 TΩ.cm2. Salt spray tests further validated these findings, showing delayed and reduced corrosion due to the protective layer formed by fGO. These results highlight the potential of fGO-modified PU coatings as advanced protective materials for steel structures in corrosive environments.

Enhancing anticorrosion performance of metals by incorporating cellulose nanofibrils/α-ZrP composite as nanofiller into water-based coating

The anticorrosion of metals has gain considerable interest in view of economic and environmental issues. Coating protection is one of the most effective and cost-effective methods for anticorrosion of metals. However, the traditional coatings often suffer from many issues such as poor performance or high cost. For the first time, a strategy was proposed by constructing cellulose nanofibrils (CNF)/alpha‑zirconium phosphate (α-ZrP) composite as nanofiller and incorporating into water-based coatings for anticorrosion of metals. The successful coordination of α-ZrP nanosheet and CNF were characterized. The effects of the resultant composite on anticorrosion performance were investigated. The results showed that, the as-prepared coating exhibited superior anticorrosion performance to commercial coatings. The impedance of the test sample coated with the as-prepared coating reached up to 4.38 × 105 Ω when it was immersed in 3.5 % NaCl solution with few corrosions fragmentation on metal surface, exhibiting a favorable long-term anticorrosion performance. Meanwhile, the anticorrosion mechanism was proposed. It is expected that this strategy would provide novel solutions for developing highly efficient water-based anticorrosive coatings of metals.

Eco-Friendly Waterborne Polyurethane Coating Modified with Ethylenediamine-Functionalized Graphene Oxide for Enhanced Anticorrosion Performance.

This study explores the potential of graphene oxide (GO) as an additive in waterborne polyurethane (WPU) resins to create eco-friendly coatings with enhanced anticorrosive properties. Traditionally, WPU's hydrophilic nature has limited its use in corrosion-resistant coatings. We investigate the impact of incorporating various GO concentrations (0.01, 0.1, and 1.3 wt%) and functionalizing GO with ethylenediamine (EDA) on the development of anticorrosive coatings for carbon steel. It was observed, by potentiodynamic polarization analysis in a 3.5% NaCl solution, that the low GO content in the WPU matrix significantly improved anticorrosion properties, with the 0.01 wt% GO-EDA formulation showing exceptional performance, high Ecorr (-117.82 mV), low icorr (3.70 × 10-9 A cm-2), and an inhibition corrosion efficiency (η) of 99.60%. Raman imaging mappings revealed that excessive GO content led to agglomeration, creating pathways for corrosive species. In UV/condensation tests, the 0.01 wt% GO-EDA coating exhibited the most promising results, with minimal corrosion products compared to pristine WPU. The large lateral dimensions of GO sheets and the cross-linking facilitated by EDA enhanced the interfacial properties and dispersion within the WPU matrix, resulting in superior barrier properties and anticorrosion performance. This advancement underscores the potential of GO-based coatings for environmentally friendly corrosion protection.

Electrolyte Formulation with Improved Ion Desolvation and Diffusion Kinetics, and Superior Anti-Corrosion Properties for Ultrawide-Temperature Supercapacitors (–70∼100°C)

Electrochemical energy storage (EES) devices operating over a wide temperature range are crucial for extreme applications like near-space exploration (–70 °C) and desert exploitation (80 °C). However, their electrochemical performance is still hindered by the high-energy-barrier desolvation process at low temperature and the parasitic redox corrosion reactions at high temperature. In this work, an ultrawide-operating-temperature-window supercapacitor is proposed by simultaneously regulating ion kinetics of electrolyte and modulating anti-corrosion property of current collector. The optimized kinetics at low temperatures (–70 °C) refer to the enhanced ion dissociation and accelerated desolvation process, which is precisely regulated by the medium dielectric constant and low donor number of both methyl propyl ketone (MPK) and methyl ethyl ketone (MEK) cosolvents. Meanwhile, the remarkable cycling stability at high temperatures (100 °C) is realized by the strengthened corrosion resistance of carbon cloth current collector. The combination of MEK/MPK based electrolyte and carbon cloth current collector enables the supercapacitor to achieve a superior low-temperature capacitance retention (91.13 % @ –60 °C and 75.4 % @ –70 °C), extended high-temperature cycling stability (69.2 % @ 100 °C, 10,000 cycles) and excellent power and energy densities (13,820 W kg–1 @ 20.68 W h kg–1). This research is expected to provide valuable references for the advanced design of EES devices with wide-operating-temperature range in future studies.

High performance coating formulation using multifunctional monomers and reinforcing functional fillers for protecting metal substrate

Purpose Effects of corrosion are very dire and mitigation of corrosion holds prime importance. Protective coatings play major role in preventing corrosion of metals and coating application is the most convenient, economical and quick solution. The purpose of the study is development of protective coatings to effectively mitigate corrosion of metal components. Design/methodology/approach A high-performance anticorrosion coating was prepared using multiple monomers and paste of functional and reinforcing fillers with extenders to protect metal components from corrosion in aggressive environmental conditions. The structures of copolymers synthesized with multiple monomers were studied by the NMR and FT-IR spectroscopic techniques. The percentage conversion of different proportions of various monomers was estimated using gas chromatography technique. The functional paste to impart superior anticorrosion properties was prepared using various functional and reinforcing fillers. The final coatings were prepared by mixing these resins with functional paste in various proportions. Findings The prepared anticorrosion coating was tested for high-performance mechanical and chemical properties and it was witnessed that the said coating offered desired performance properties needed for protecting metal components from corrosion. Research limitations/implications As such it is overcoming drawbacks of two pack systems and thus has almost no limitations or implications for application on metal substrate. Practical implications Being formulated as a single pack, it is free from drawbacks otherwise involved in two pack system of conventional paints. The coating system developed is very easy to apply using conventional tools, namely, brush, spray and roller techniques. The formulation is made in such a way that it has fast-drying properties. Makes painting or coating operations cost effective and confirm the performance. Social implications The findings of the research have anticorrosion nature that can enhance the life span of the substrates. It is specially designed for metal substrate and can protect metal substrate from corrosion in most aggressive conditions. Thus, it helps to reduce losses due corrosion and increase safety of metal structures and human being as well. As it is based on conventional material but with new formulation and technology, it has commercial possibilities to explore. Originality/value Unlike conventional protective coating systems, the said coating offered disruptive features like single pack systems and fast drying at ambient temperature along with high-performance properties. The coating formulation was observed to have a great importance in industry for effective corrosion mitigation and to reduce losses due to corrosion.

The Synergistic Effect of Graphene Oxide in Epoxy Resin on Photocured Coating Films with Anticorrosion and Antibacterial Properties.

In this work, graphene oxide (GO) and epoxy-functionalized graphene oxide (GOSi) are chosen as additives and incorporated into epoxy resin (EP) for nanocomposite photo-coating films (GO/EP and GOSi/EP series). Compared to GO/EP, the GOSi/EP nanocomposite demonstrates strong binding and excellent dispersibility, highlighting covalent bonding between GOSi and the epoxy coating. Furthermore, GOSi/EP-based films demonstrated superior thermal stability and adhesion performance on galvanized steel plates. The corrosion performance of the coated galvanized steel is investigated using electrochemical impedance spectroscopy (EIS) and polarization curve analysis (Tafel). The effectiveness of corrosion protection is evaluated based on a combination of photoreactivity, crosslinking density, dispersity, and adhesion properties. Out of all the treated films, the film based on 0.1GOSi/EP exhibited the highest percentage of inhibition (98.89%) and demonstrated superior long-term anticorrosion stability. In addition, the 0.1GOSi/EP based formulation showed remarkable antibacterial activity against S. aureus, resulting in a 92% reduction. This work demonstrates the development of a facile, environmentally friendly functionalized graphene oxide/epoxy photocured film with superior dual functionalities in both anticorrosion and antibacterial properties. These advancements hold promising potential for impactful practical applications.

Near-range modulation of single-atomic Fe sites by simultaneously integrating heteroatom and nanocluster for efficient oxygen reduction

Modulation strategies are widely developed to regulate electronic state of single-atom catalysts (SACs) to reinforce the catalytic activity of oxygen reduction reaction (ORR). However, the modulation effect using only single coordination regulation is often insufficient to optimize the electronic and geometric structure of metal active centers. Herein, a general strategy to modify the activity of single-atomic Fe site is achieved by dual decoration of Fe centers with contiguous sulfur atoms and metal nanoclusters via an aggregation-redispersion route. Under near-range engagement, the adjacent S atoms and Fe nanoclusters can break the symmetric electronic interface of Fe-N moiety, and act as the modulators to synergistically tune the electronic configurations of Fe centers, leading to less electron transfer to *OH, and subsequent favorable desorption. In situ spectroscopic characterization and theoretical results reinforces the significant roles of S atoms and metal clusters in tandem by correlating their induced electron redistribution with ORR activity, which ultimately accelerates the adsorption/desorption of oxygenated intermediates for robust catalytic performance. Due to the improvement of graphitization degree, carbon supports possess efficient active sites and exhibit superior anti-corrosion. The resultant FeNC-2 M demonstrates outstanding ORR activity with high power density, maintaining remarkable durability in Zn-air batteries and microbial fuel cells. This work provides effective and universal way to modulate microenvironment of single metal sites, facilitating the open up of potential application spaces for various SACs.

ZIF-8 based bifunctional coatings with anticorrosive and antibacterial properties: A new design strategy for more efficiency

An efficient and simple in-situ/mechanical two-step strategy has been discovered for the fabrication of nanocontainers based on zeolite imidazole framework-8 (ZIF-8) with corrosion inhibitors (benzotriazole, BTA). The nanocontainers were applied in anticorrosive coatings with anticorrosion and antibacterial bifunctions for aluminum alloys AA2024. The effects of ZIF-8 modified with the corrosion inhibitor via different methods (in-situ, mechanical, and two-step strategies) on its morphology, composition, structure, loading/release behavior were studied and discussed. Results showed that the amount of loaded BTA was positively correlated with the crystal size of the final ZIF-8, impacting sustained release. Compared with the conventional primary load (in-situ and mechanical loading way), the two-step loading method (in-situ followed by mechanical treatment) achieved a higher BTA loading without evident ZIF-8 morphology and structure changes. The two-step modified (2-BTA@ZIF-8) powders exhibited good corrosion inhibition and remarkable antibacterial properties against Escherichia coli and Staphylococcus aureus. Additionally, the 1-BTA@ZIF-8 (in-situ strategy), 1-BTA/ZIF-8 (mechanical strategy) and 2-BTA@ZIF-8 composites were dispersed in acrylic resin to prepare anticorrosive and antibacterial bifunctional coatings. Results showed that the 2-BTA@ZIF-8 incorporated acrylic coatings exhibited superior anticorrosion performance and antimicrobial activity compared to the unmodified coating due to the controlled release of BTA. Thus, elaborated strategy represents a feasible and effective way to construct high-performance anticorrosive and antimicrobial coatings with metal-organic framework materials.

S-NiSe/HG Nanocomposites with Balanced Dielectric Loss Encapsulated in Room-Temperature Self-Healing Polyurethane for Microwave Absorption and Corrosion Protection.

Exploring anticorrosion electromagnetic wave (EMW) absorbing materials in harsh conditions remains a challenge. Herein, S-NiSe/HG nanocomposites encapsulated in room-temperature self-healing polyurethane (S-NiSe/HG/SPU) were exploited as superior anticorrosion EMW absorbing materials. A dual-defect engineering collaborative Schottky interface construction endows S-NiSe/HG with a high vacancy concentration, abundant defects, and moderate conductivity. These structural merits synergistically balance dielectric loss by enhancing dipole-interface polarization loss and optimizing conduction loss. As a result, S-NiSe/HG demonstrates the optimal EMW absorption performance with a minimum reflection loss (RLmin) of -54.8 dB and an adequate absorption bandwidth (EAB) of 7.1 GHz. Besides, S-NiSe/HG/SPU combines the maze effect of S-NiSe/HG with the active repair capability of SPU, thereby providing long-term corrosion resistance for the Mg alloy. Even under corrosion for 10 days, S-NiSe/HG/SPU affords a low corrosion current density (1.3 × 10-5 A) and high charge transfer resistance (3796 Ω cm2). Overall, this work provides valuable insights for in-depth exploration of dielectric loss and development of multifunctional EMW-absorbing materials.

Synthesizing Benzotriazole Group-Terminated Carbon Dots as Multifunctional Additives of Poly(ethylene glycol).

Long running-in period and corrosion problems have greatly hindered the practical applications of poly(ethylene glycol) (PEG) lubricants. In this work, benzotriazole group-terminated carbon dots (BT-CDs) were specifically synthesized through a facile solvothermal method. The benzotriazole groups on BT-CD surfaces not only imparted them excellent dispersibility in the PEG base oil but also brought in outstanding anticorrosion ability for BT-CDs. With the aid of the coordination effects between benzotriazole groups and metal atoms, the BT-CDs could quickly and solidly adsorb onto the steel surface to form a dense adsorption layer, which resulted in an amazing phenomenon, i.e., the disappearance of the running-in period for the friction test. Adding 5.0 wt % BT-CDs reduced the friction and wear of PEG200 by 49.16 and 49.52%, respectively. When the duration was prolonged from 20 to 120 min, these values were further enlarged to 53.77 and 60.71%. The worn surface characterization demonstrated that the BT-CDs induced the generation of robust lubricating films on the frictional interfaces, accounting for their distinguished tribological performance. Considering the superior anticorrosion ability and the potential possibility of avoiding the running-in period, the BT-CDs are expected to be developed as particularly promising additives toward PEG.

Environmentally Benign Grape Seed Oil for Corrosion Inhibition: Cutting-Edge Computational Modeling Techniques Revealing the Intermolecular and Intramolecular Synergistic Inhibition Action

The growing interest in eco-friendly alternatives has sparked research into essential oils as corrosion inhibitors, offering an innovative approach. Investigating their unique properties, researchers aim to advance corrosion engineering for a sustainable future. Despite promising lab results, the exact mechanism of their action in corrosion engineering is not fully understood, highlighting the need for further exploration. Using computational modeling, we explored how grape seed oil (GSO) compounds interact with carbon steel (C38) surfaces, unraveling the inhibitive properties against corrosion. Employing various simulation methods, such as density functional theory (DFT), density functional-based tight-binding (DFTB), and molecular dynamics (MD), this study validates experimental findings and unveils novel insights into the underlying mechanisms of these interactions. Quantitative analysis quantifies the inter- and intramolecular synergistic effect and suggests that the LA@OA promotes the charge-transfer process. DFTB calculations reveal that the synergistic action in the parallel adsorption configuration of LA and OA molecules is sufficiently strong to form a stable adsorption layer on the Fe surface with a large negative value of Eads (6.74 eV). Experimental results demonstrated that the inhibition performance of GSO extract exhibited a notable increase with increasing concentrations, reaching a higher efficiency of 79% at 0.5 g/L of GSO. EIS results demonstrated that the existence of the GSO inhibitor film increases the resistance of the charge transfer (about 80 Ω cm2 at 0.5 g/L), indicating the superior barrier anticorrosion properties of the formed film. The theoretical results validate the exceptional anticorrosion performance and provide compelling evidence of the remarkable ability to prevent corrosion of C38 substrate. The findings offer potential pathways for the development of eco-friendly alternatives and interestingly provide a foundation understanding in the field.

Biohybrid microcapsules based on electrosprayed CS-immobilized nanoZrV for self-healing epoxy coating development.

In this work, zirconium vanadate nanoparticles were immobilized into chitosan using a facile electrospraying technique to produce CS-ZrV hybrid microcapsules for the development of a self-healing coating. Upon assessment, hybrid microcapsules possessed desirable properties with a mean particle size of 319 μm, maintaining good thermal stability of ∼55% at 700 °C, and were subsequently incorporated into an epoxy resin to develop a biocompatible self-healing coating, CZVEx, for carbon steel corrosion protection. Scratched samples of self-healing and control coatings were analyzed in a corrosion medium of 3.5 wt% aqueous NaCl. SEM images of the scratched coating sample, after days of immersion, revealed healing of defects through the appearance of an epoxide gel-like substance due to the release of polymeric vanadate that reacted with corrosion agents, resulting in polymerization of vanadium hydrates and subsequent self-healing, validated by the proposed mechanism of self-healing. Electrochemical impedance spectroscopy analysis further confirmed CZVEx coating possessed excellent self-healing capabilities through a significant impedance rise from 4.48 × 105 to 5.52 × 105 (ohm cm2) between the 7th and 14th day of immersion. Furthermore, comparative polarization assessment of coating samples with/without defects indicated the accuracy of EIS for self-healing analysis, and showed the sample with no defect was only 2.6 times more corrosion resistant than the scratched coating, as against bare steel substrate that was 22 times less resistant, revealing superior self-healing anticorrosion properties of the coating.

Porous metal microsphere M@C-rGO (metal = Mn, Fe, Co, Ni, Cu) aerogels with high low-frequency microwave absorption, strong thermal insulation and superior anticorrosion performance

Porous metal microsphere M@C-rGO (metal = Mn, Fe, Co, Ni, Cu) aerogels with high low-frequency microwave absorption, strong thermal insulation and superior anticorrosion performance are successfully constructed.