ABSTRACT
Biomimetic slippery liquid-infused porous surfaces (SLIPS) have emerged as a promising solution to solve the limitations of superhydrophobic surfaces, such as inadequate durability in corrosion protection and a propensity for frosting. However, the challenge of ensuring strong, lasting adhesion on diverse materials to enhance the durability of the lubricant layer remains. The research addresses this by leveraging amyloid phase-transitioned lysozyme (PTL) as an adhesive interlayer, conferring stable attachment of SLIPS across a variety of substrates, including metals, inorganics, and polymers. The silica-textured interface robustly secures the lubricant with a notably low sliding angle of 1.15°. PTL-mediated adhesion fortifies the silicone oil attachment to the substrate, ensuring the retention of its repellent efficacy amidst mechanical stressors like ultrasonication, water scrubbing, and centrifugation. The integration of robust adhesion, cross-substrate compatibility, and durability under stress affords the PTL-modified SLIPS exceptional anti-fouling, anti-icing, and anti-corrosion properties, marking it as a leading solution for advanced protective applications.
ABSTRACT
The giant reduction of the barrier properties due to self-healing microcapsules and the lack of real-time protection during the healing remained the main challenges in self-healing anticorrosion coatings. Herein, a facile strategy using Janus graphene oxide (GO) as a dense and flexible shell has been proposed to synergistically solve these challenges. Benzotriazole (BTA) was used to synthesize Janus GO at the oil-water interface, and Janus GO/BTA/poly(methyl methacrylate) microcapsules were prepared. Energy-dispersive X-ray spectroscopy, Fourier infrared spectroscopy, Raman spectroscopy, and ultraviolet spectrophotometer analysis confirmed the formation of a Janus GO structure with one surface hydrophilic and the other hydrophobic. The surface morphology of J-GO-capsules with a high GO coverage rate was observed by scanning electron microscopy. The high biobased content coating containing J-GO-capsules showed a low-frequency impedance value above 1010 as assessed by electrochemical impedance spectroscopy after being immersed in 3.5 wt % NaCl solution for 60 days. In addition, the low-frequency impedance values of the coating were maintained after being scratched due to the self-healing properties of the J-GO-capsules as well as the real-time protective effect of the BTA. Biobased coatings with the best overall properties among all of the self-healing anticorrosion coatings were prepared.
ABSTRACT
This article aims to develop CeO2 nanocontainer-constructed coating with a synergistic self-healing and protective nature through a simple mechanical blending technique to manage metal corrosion. The proposed coating exhibits excellent corrosion resistance, which is primarily attributed to the combination of thermal-driven healing and active corrosion inhibition. Paraffin wax and 2-polybenzothiazole-loaded CeO2 nanotubes (CeO2-MBT) are directly doped into epoxy coating to perform such a multifunctional role. CeO2 nanocontainers and encapsulated corrosion inhibitor MBT can be released by pH triggers to achieve instant corrosion inhibition upon the surface of metal substrate. In addition, any physical defects in the coating are responsively repaired by heating incorporated paraffin wax to regain structural integrity and consequent barrier function. Corrosion protection efficiency remains sufficient even after ten cycles of damage and healing. Such a multiple-functional coating strategy provides an alternative pathway toward efficient and sustainable performance to tackle corrosion-related challenges of metal components in both short-term and long-term services.
ABSTRACT
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.
ABSTRACT
In this study, we developed a composite material comprising UIO-66-NH2 encapsulated tannic acid (TA) loaded on Ti3C2Tx to improve the corrosion resistance of water borne epoxy (WEP) coatings. The successful synthesis of the material was determined by FT-IR, XRD, XPS, EDS, TGA, SEM and TEM characterization. Furthermore, ultraviolet (UV)tests were conducted to evaluate the release rate of TA at varying pH levels, revealing a release rate of approximately 95 % at pH 2. Electrochemical impedance spectroscopy (EIS) results over 60 d indicated that the Rc value of TU-T/WEP remained unchanged at 3.934 × 108, demonstrating a two-order magnitude increase compared to those of pure epoxy coatings, attributed to the synergistic active and passive protection of TU-T materials. The self-healing ability of the TU-T/WEP coating was validated through manual scratch experiments. Additionally, the EIS test showed that the Rc value of TU-T/WEP coating increased to 3.5 × 105 after 72 h, representing a two-order magnitude increase over that of the WEP coating alone. This study introduces a novel approach using green tannic acid as a corrosion inhibitor and amino-functionalized Ti3C2Tx with UIO-66-NH2 to enhance corrosion resistance and self-healing aproperties of coatings.
ABSTRACT
Single-layer isophorone diisocyanate (IPDI) are one of the most popular self-healing microcapsules but suffers from low shell strength, poor heat resistance, stability and aging properties. In this paper, IPDI microcapsules were encapsulated into double-layer phenolic (PF)/polyurethane (PU) by a two-step process involving interfacial polymerization and in-situ polymerization. The prepared microcapsule composites were comprehensively characterized for their physical and chemical properties using optical microanalysis, scanning electron microscope, Fourier transform infrared spectroscopy, thermal gravimetric analysis and depth-sensing indentation analysis. Compared with the single-layer PU-IPDI microcapsule counterpart, the mechanical performance, thermal resistance, aging property and environmental stability of double-layer PF/PU-IPDI microcapsules were significantly improved. The epoxy coating was enhanced with the incorporation of 10 wt.% PF/PU-IPDI microcapsules, whose self-healing performance was evaluated by scratch corrosion test. The results demonstrated successful repair of coating scratches, along with the absence of corrosion on the coated steel substrate soaked in a 10 wt.% NaCl solution for 7 days. By comparing the tensile strength of epoxy coating before and after crack formation, it could be found that the self-healing efficiency was 57.9% when loaded with 10 wt.% of PF/PU-IPDI microcapsules in coating. This study highlights that the rational design of double-layer microcapsules integrated into the epoxy coating matrix could provide excellent anti-corrosion and self-healing properties.
ABSTRACT
Under purely inorganic conditions, a synthesis route was devised wherein elements were introduced stepwise via coprecipitation based on differences in compound solubility. This synthesis method can change the microscopic morphology of the material without relying on a templating agent, resulting in the formation of the multilayered lamellar Ce/Eu codoped zinc oxide solid solution (ZCEOSS) with a self-assembled nested imbrication structure. The study improves the critical matter of corrosion by focusing on the electron and energy transfer mechanisms. By introduction of the bandgap modulator cerium element and fluorescence enhancer europium element into the ZnO material, the anticorrosion material has been successfully endowed with both photocathodic protection and luminescent initiative/stress dual corrosion defense functions. Due to the energy level staircase protection mechanism synergistically generated by the 4f electron shell of rare-earth elements in concert with semiconductor zinc oxide, the energy band positions were modulated to progressively guide the direction of electron flow, thereby suppressing corrosion reactions. In particular, the ZCEOSS material synthesized by doping 1% cerium and 7% europium and adding rare-earth elements at pH 7 exhibited the best corrosion inhibition performance. After immersion in simulated seawater for 96 h, Tafel polarization test results showed that compared to epoxy resin and ZnO anticorrosion systems, the ZCEOSS anticorrosion system exhibited significantly improved corrosion inhibition efficiency with enhancements of 1028.3 and 402.9%, respectively. This study provides new insights into the development of highly efficient inorganic anticorrosion materials.
ABSTRACT
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 shows promising resistance against bacteria, algae and proteins, as well as excellent corrosion resistance in artificial seawater. The coating also exhibits excellent chemical resistance in organic solvents as well as neutral and alkaline environments. Moreover, its controlled degradation after 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 marine engineering fields.
ABSTRACT
In this paper, the effects of the SiC phase incorporated in Ni substrate deposits on storage tank steel during electrodeposition at different current densities are explored. The microstructure, phase content, and corrosion resistance of the resulting Ni-SiC composites were investigated by scanning electron microscopy (SEM) matched with energy disperse spectroscopy (EDS), X-ray diffraction (XRD), and an electrochemical workstation, respectively. SEM micrographs and EDS results show that at 2.5 A/dm2, the composites presented a smooth and compact structure with high SiC content, while at 1.8 or 3.2 A/dm2, it became uneven and loose in structure with low SiC content. XRD patterns showed that the nickel grain size of composites firstly increased and then decreased with the growth of the current density. Notably, the Ni-SiC composite produced at 2.5 A/dm2 possessed a higher corrosion potential (-0.507 V) and lower corrosion current density (2.439 µA/cm2), illustrating that its excellent anti-corrosion ability was superior than that of other two composites. Hence, SiC co-deposited at 2.5 A/dm2 conducted as a protective barrier and inhibited the corrosion rate against a corrosion medium of Cl- and SO42- ions. In addition, the corrosion relationship illustrated that the SiC content of Ni-SiC composite firstly increased and then decreased with the growth of the current density, while the corrosion weight loss of Ni-SiC composites firstly decreased and then increased.
ABSTRACT
The pursuit of carbon-neutral energy has intensified the interest in green hydrogen production from direct seawater electrolysis, given the scarcity of freshwater resources. While Ni-based catalysts are known for their robust activity in alkaline water oxidation, their catalytic sites are prone to rapid degradation in the chlorine-rich environments of seawater, leading to limited operation time. Herein, we report a Ni(OH)2 catalyst interfaced with laser-ablated LiFePO4 (Ni(OH)2/L-LFP), derived from spent Li-ion batteries (LIBs), as an effective and stable electrocatalyst for direct seawater oxidation. Our comprehensive analyses reveal that the PO4 3- species, formed around L-LFP, effectively repels Cl- ions during seawater oxidation, mitigating corrosion. Simultaneously, the interface between in situ generated NiOOH and Fe3(PO4)2 enhances OH- adsorption and electron transfer during the oxygen evolution reaction. This synergistic effect leads to a low overpotential of 237â mV to attain a current density of 10â mA cm-2 and remarkable durability, with only a 3.3 % activity loss after 600â h at 100â mA cm-2 in alkaline seawater. Our findings present a viable strategy for repurposing spent LIBs into high-performance catalysts for sustainable seawater electrolysis, contributing to the advancement of green hydrogen production technologies.