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Exploring the plasmon energy dissipation mechanism of bimetallic nanostructures after photoexcitation is of great significance for controlling energy transfer in plasmonic applications. The absorption, scattering, and extinction spectra of Ag@Cu, Ag@Pt, and Ag@Co core–shell nanostructures are calculated by finite element method, and the energy dissipation process is visualized by using particle trajectory and the absorbed power density distribution. The absorption/scattering ratio of the core–shell nanostructures, the shell absorptivity, the time-domain electric field as well as the extra-core electron arrangements of Ag, Cu, Pt, and Co atoms are analyzed for figuring out the energy dissipation mechanism. The results show that when a non-plasmonic metal is coated on the surface of a plasmonic metal, the plasmon energy dissipates preferentially in the shell, and the degree of dissipation depends on the imaginary part of the dielectric constant of the shell and the core. A larger dielectric constant of the shell can cause more energy to be transferred from the plasmonic metal to the shell region. This study provides the fundamental physical framework and design principles for plasmonic nanostructures. [ABSTRACT FROM AUTHOR]

Thin films of amorphous silicon (a-Si) coated on metals such as nickel (Ni) are one of the most promising anode architectures for high-energy-density lithium-ion (Li-ion) batteries. The performance and longevity of batteries with this type of electrode depend on the integrity of the Ni/a–Si interface. The integrity of the a-Si /Ni bonded interface during cycling is critical, but the experimental characterization of interfacial failure of this material system is highly challenging and there is a sparsity of interface strength data in the literature. Here, we describe a laser spallation (LS) technique to characterize the interfacial adhesion strength of Ni/a–Si multilayer films created by chemical vapor deposition (CVD). The LS technique enables the non-contact measurement of the tensile interfacial strength with high precision when compared to conventional methods for characterizing adhesion. Interferometric measurement combined with finite element analysis shows that the Ni/a–Si interface, created via the CVD of a-Si on Ni surfaces can withstand ≈46–72 MPa in tension before failure initiation. To ensure successful and precise characterization of interfacial adhesion strength using LS, we further develop a design criterion for multi-layer samples by analyzing the thin-film mechanics. Our study provides insights into the strength of the Ni/a–Si interface that governs the performance and durability of high-energy-density anodes and offers design guidelines for improving thin-film electrode integrity. [ABSTRACT FROM AUTHOR]

The rapid realization of efficient anti-icing coatings on diverse substrates is of vital value for practical applications. However, current approaches for rapid preparations of anti-icing coatings are still deficient regarding their surface universality and accessibility. Here, we report a simple processing approach to rapidly form icephobic liquid-like polydimethylsiloxane (PDMS) brushes on various substrates, including metals, ceramics, glass, and plastics. A poly(dimethylsiloxane), trimethoxysilane is applied as a reactant under the catalysis of a minimal amount of acid formed by hydrolysis of dichlorodimethylsilane. With such an advantage, this approach is approved to be applicable of coating metal surfaces with less corrosion. The distinctive flexibility of the PDMS chains provides a liquid-like property to the coating showing low contact angle hysteresis and ice adhesion strength. Notably, the ice adhesion strength remains similar across a wide temperature window, from −70 to −10 °C, with a value of 18.4 kPa. The PDMS brushes demonstrate perfect capability for resisting acid and alkali corrosions, ultra-violet degradation, and even tens of icing/deicing cycles. Moreover, the liquid-like coating can also form at supercooling conditions, such as −20 °C, and shows an outstanding anti-icing/deicing performance, which meets the in situ coating reformation requirement under extreme conditions when it is damaged. This instantly forming anti-icing material will benefit from resisting instantaneous ice accretion on surfaces under extremely cold conditions. [ABSTRACT FROM AUTHOR]

The transition metal silicide coatings have excellent oxidation resistance. In the high-temperature oxidization environment, the "anomalous" diffusion phenomenon of the reverse concentration gradient occurs in the multilayer silicide coating structure, which has a significant impact on the coating degradation. This study is to explore the physical mechanism of "anomalous" diffusion phase transformation in the MoSi2–NbSi2 bilayer silicide coating on the Nb alloy substrate. Through vacuum annealing experiments, combined with micro-Raman spectroscopy and electron probe microanalysis measurements, the diffuisonal phase transformation of multilayer silicide coating in the oxygen-free environment at high temperatures was studied. By decoupling the oxidation and diffusion, the experiments indicate that high-temperature oxidation is not the dominant driving factor for the "anomalous" diffusion of atoms. The thermodynamic analysis reveals that the reduction in the nucleation barrier of the silicide-poor layer due to multicomponent solid solution and the non-uniform distribution of component chemical potential provide the driving force for the "anomalous" diffusion growth. Based on the diffusion kinetic modeling, the simulation of diffusion-controlled phase transformation in multilayer silicide coating was carried out, and the effect of tracer diffusion coefficients on the growth of the silicide-poor phase was analyzed. The research will have guiding significance for the recognition of failure mechanisms of silicide coating systems and performance improvement. [ABSTRACT FROM AUTHOR]

Fly ash cenospheres serve as an inexpensive filler for various composites. Coating their surface with metal significantly alters the properties of the resulting composites. In this study, aluminosilicate cenospheres receive a copper coating using a plasma method with magnetron sputtering. Based on these copper-coated cenospheres, composites are created, and their dielectric properties are investigated in a parallel plate capacitor cell under isotropic pressures ranging from 1 to 75 atm. Composites based on pure fly ash cenospheres exhibit pressure-invariant properties, including the dielectric constant and loss factor. However, for composites based on copper-coated fly ash cenospheres, an abrupt increase in electrical conductivity is observed as the pressure increases. Interestingly, significant changes in electrodynamics characteristics are not detected under the influence of anisotropic stress. The methodology tested in this work can be utilized for creating smart materials based on cenospheres. [ABSTRACT FROM AUTHOR]

The rapid growth of the dye industry and the worsening water resource crisis have drawn significant focus to the treatment of dye wastewater. Membrane separation technology is increasingly being utilized in addressing this issue. However, traditional separation membranes face challenges such as susceptibility to contamination and significant decline in subsequent separation permeance. This work utilizes a straightforward brushing technique to effectively apply a coating comprising titanium dioxide (TiO2) nanoparticles and attapulgite (APT) onto a stainless steel mesh (SSM), equipping it with the capability for dye adsorption and separation. Studies show that coatings with different ratios yield varying degrees of coverage on the SSM. A higher concentration of TiO2/attapulgite results in improved coverage on the SSM, creating a denser coating on the mesh surface and the degree of cross-linking of the coating was as high as 92.22%. The coated meshes exhibited superhydrophilicity uniformly and excellent negatively charged properties. Separation experiments of the meshes with different TiO2/attapulgite ratios were conducted by separating simulated dye wastewater with methylene blue (MB) and safranine T (SaT). The results indicate that the prepared meshes achieved a maximum rejection of over 98.0% for MB and over 96.5% for SaT. In addition, the prepared meshes maintained high dye rejection efficiencies (>96%) even after 10 consecutive separation cycles. The above results indicate that the prepared meshes are promising for application in industrial dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V metal is widely used as an implantable material due to its biocompatibility and corrosion resistance; however, it has low bioactive properties. The formation of nanotubes and a hydroxyapatite-polyvinyl alcohol-collagen composite coating on Ti-6Al-4V metal aims to enhance its biocompatibility and bioactivity. The nanotube oxide layer Ti-6Al-4V was formed by the anodization method. The composite’s infrared spectrum showed characteristic absorption bands from Hydroxyapatite (HAp), polyvinyl alcohol, and collagen. The composite-coated Ti-6Al-4V metal, both non-nanotube, and nanotube, showed a typical diffraction pattern of HAp and titanium element. The electron microscope image showed the uniform granular form of HAp. The corrosion test results showed that composite-coated nanotube Ti-6Al-4V metal could not improve corrosion resistance. It is also relevant to the in vitro test in a lactate ringer solution that showed the higher Ca2+ ion of nanotube Ti-6Al-4V metal than that of non-nanotube Ti-6Al-4V metal. [ABSTRACT FROM AUTHOR]

In almost all electrochemical systems for electrochemiluminescence (ECL) analysis, electrodes are connected with an external power source, either directly or via wireless energy transfer circuit. That is inconvenient and makes some applications impossible. Herein, we use galvanized iron with two different metals as both power source and electrodes to achieve a self‐powered ECL and exploit ECL for the imaging of the corrosion of protective coating of widely used metal (e.g. galvanized iron) for the first time. The self‐powered ECL enables the visualization of the deterioration of galvanic coating on iron using a smartphone and the detection of ascorbic acid with a linear range of 0.5–100 μM and a limit of detection of 0.31 μM. The devices based on self‐powered approach do not require external power supply, thus effectively reducing their volume and cost. The self‐powered ECL holds great promise for metal corrosion imaging and analytical applications. [ABSTRACT FROM AUTHOR]

Herein, a core–shell structured nanocomposite with excellent electrorheological (ER) properties was successfully prepared for studying ER fluids (ERFs). First, the material was prepared by using chromium (Cr)-ion-doped Ti-based metal–organic frameworks (MOF-Ti) as a template using the solvothermal method, followed by coating with SiO 2 via hydrolysis to form Cr-MOF-Ti/SiO 2 composite. In combination with the advantages of the MOF-Ti structure, such as more active sites and a high specific surface area, doping with transition metal ions and coating with SiO 2 can effectively enhance the interfacial polarisation of the obtained Cr-MOF-Ti/SiO 2 composite and thus improve its ER performance. Analyses were conducted on the morphology, elemental composition and functional groups of the materials using scanning electron microscopy, transmission electron microscopy, X-ray diffractometer, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller and dielectric analysis. The results indicate successful Cr-ion doping and SiO 2 coating. The ER performance of the composite particles was also evaluated. The results indicate that the SiO 2 -coated sample exhibits superior ER properties, including a smaller leakage current density and higher shear stress. Moreover, the SiO 2 coating enhanced the interfacial polarisation capability of Cr-MOF-Ti, as verified by the dielectric data. [ABSTRACT FROM AUTHOR]

The efficiency of drug delivery from coatings of metallic implants is one of the key factors. The influence of chemical and thermal treatments of nitinol wire on the corrosion properties, deposition of hydroxyapatite(HA)/poly ε-caprolactone-polyethylene glycol (PEG-b-PCL), and the amount of ibuprofen released from that bilayer were studied. The hydroxyapatite layer was electrodeposited by pulse current, while the PEG-b-PCL layer was by drop-coating. It was shown that nitinol wire, chemically treated and thermally heated at 470 °C under optimized conditions, is the most optimal substrate for the deposition of uniform and compact hybrid HA/(PEG-b-PCL) bilayer. Ibuprofen incorporated into this hybrid bilayer exhibits the maximum release into phosphate-buffered saline (PBS) solution. About 80% of ibuprofen is released within 5 h. [ABSTRACT FROM AUTHOR]

This study examined the potential application of metallic coatings to mitigate the adverse effects of ultraviolet (UV) and infrared (IR) light on photovoltaic modules. Titanium coatings were applied on low-iron glass surfaces using magnetron sputtering at powers of 1000, 1250, 1500, 1750, 2000, and 2500 W. The module with uncoated glass served as a reference. The Ti layer thickness varied from 7 nm to 20 nm. Transmittance and reflectance spectra were used to calculate visible light transmittance Lt, UV light transmittance Ltuv, solar transmittance g, and visible light reflectance Lr. The obtained parameters indicated that the thinnest Ti layer (1000 W) coating did not significantly affect light transmittance, but thicker layers did, altering the Lt, g, and Lr factors. However, every sample noticeably changed Ltuv, probably due to the natural formation of a UV-reflective thin TiO2 layer. The differences in fill factor (FF) were minimal, but thicker coatings resulted in lower open-circuit voltages (Uoc) and short-circuit currents (Isc), leading to a reduction in power conversion efficiency (PCE). Notably, a Ti coating deposited at 2500 W reduced the power of the photovoltaic module by 78% compared to the uncoated sample but may protect modules against the unwanted effects of overheating. [ABSTRACT FROM AUTHOR]

Surface engineering is one of the most extensive industries. Virtually all areas of the economy benefit from the achievements of surface engineering. Surface quality affects the quality of finished products as well as the quality of manufactured parts. It affects both functional qualities and esthetics. Surface quality affects the image and reputation of a brand. This is particularly true for cars and household appliances. Surface modification of products is also aimed at improving their functional and protective properties. This applies to surfaces for producing hydrophobic surfaces, anti-wear protection of friction pairs, corrosion protection, and others. Metal technologies and 3D printing benefit from surface technologies that improve their functionality and facilitate the operation of products. Surface engineering offers a range of different coating and layering methods from varnishing and painting to sophisticated nanometric coatings. This paper presents an overview of selected surface engineering issues pertaining to metal products, with a particular focus on surface modification of products manufactured by 3D printing technology. It evaluates the impact of the surface quality of products on their functional and performance qualities. [ABSTRACT FROM AUTHOR]

This paper presents a simple, fast, and cost-effective method for creating metallic microstructured surfaces by spray-coating a dispersion of copper nanoparticles (CuNPs) onto polymethyl methacrylate (PMMA) substrates, enabling the imbibition-induced wetting of liquid metal. The formation of these microstructured patterns is crucial for the spontaneous wetting of gallium-based liquid metals. Traditional techniques for producing such microstructures often involve complex and costly lithography and vacuum deposition methods. In contrast, this study demonstrates that liquid metal wetting can occur with metal microstructures formed through a straightforward spray-coating process. To immobilize the CuNPs on the polymer substrate, an organic solvent that dissolves the polymer surface was employed as the dispersion medium. The effects of various spray-coating parameters, including distance and time, on the uniformity and immobilization of CuNP films were systematically investigated. Under optimal conditions (120 s of spray time and 10 cm spray distance), CuNPs dispersed in dichloromethane (DCM) yielded uniform and stable microstructured surfaces. The spontaneous wetting of gallium-based liquid metal was observed on the fabricated CuNP film. Additionally, liquid metal selectively wet the CuNP patterns formed by stencil techniques, establishing electrical connections between electrodes. These findings underscore the potential of spray-coating for fabricating metallic surfaces to drive the formation of liquid metal patterns in flexible electronics applications. [ABSTRACT FROM AUTHOR]

Metallization, a process for applying anti-corrosion coatings, has advantages over hot-dip galvanizing, such as reduced thermal stress and the ability to work "in situ". This process consists of the projection of a protective metal as coating from a wire as application material, and this wire is obtained by multi-stage wiredrawing. For the metallization process, a zinc–aluminum alloy wire obtained by this process is used. This industrial process requires multiple stages/dies of diameter reduction, and determining the optimal sequence is complex. Thus, this work focuses on developing models with the aim of designing and optimizing the wiredrawing process of zinc–aluminum (ZnAl) alloys, specifically ZnAl15%, used for anti-corrosion applications. Both analytical models and numerical models based on the finite element method (FEM) and implemented by computer-aided engineering (CAE) software Deform 2D/3D v.12, enabled the prediction of the drawing stress and drawing force in each drawing stage, producing values consistent with experimental measurements. Key findings include the modeling of the material behavior when ZnAl15% wires were subjected to the tensile test at different speeds, with strain rate sensitivity coefficient m = 0.0128, demonstrating that this type of alloy is especially sensitive to the strain rate. In addition, the optimal friction coefficient (µ) for the drawing process of this material was experimentally identified as µ = 0.28, the ideal drawing die angle was determined to be 2α = 10°, and the alloy's deformability limit has been established by a reduction ratio r ≤ 22.5%, which indicates good plastic deformation capacity. The experimental results confirmed that the development of the proposed models can be feasible to facilitate the design and optimization of industrial processes, improving the efficiency and quality of ZnAl15% alloy wire production. [ABSTRACT FROM AUTHOR]

Surface modifications not only improve the corrosion resistance of Co-Cr-Mo dental alloys (Bego Wirobond® C) but also ensure their long-term performance and reliability in dental applications. This paper describes the preparation of single-layer TiO2-ZrO2 sol–gel coatings on the Co-Cr-Mo dental alloy using the method of dip-coating. The TiO2-ZrO2 sol–gel coatings were sintered at 300 and 500 °C. SEM analysis shows that sintering at 300 °C produces a uniform, slightly dense structure without micro-cracks, while sintering at 500 °C results in a denser structure with micro-cracks due to higher stress and shrinkage. EDS confirms that sintering temperature affects the elemental composition of the coating, with higher temperatures causing the volatilization or diffusion of Ti and Zr. Roughness measurements indicate that the Ra value increases with the sintering temperature, meeting dental application requirements. Electrochemical measurements by open-circuit potential, EIS, and cyclic potentiodynamic curves demonstrate that sintering temperature and saliva composition affect corrosion resistance, with NaF and mouthwashes (Listerine Total Care Teeth Protection® and Meridol®) generally increasing charge transfer resistance and double-layer capacitance. The ceramic TiO2-ZrO2 coatings significantly reduce pitting corrosion susceptibility at physiological and acidic pH, with the 500 °C sintered coating showing better protective properties. These findings highlight the potential of TiO2-ZrO2 coatings in enhancing the performance of Co-Cr-Mo dental alloys. [ABSTRACT FROM AUTHOR]

Wire Arc Additive Manufacturing (WAAM) technology, known for its low equipment and material costs, high material utilization, and high production efficiency, has found extensive applications in the fabrication of key components for the aerospace and aviation industries. The stability of the arc is crucial for the WAAM process as it directly affects the forming of the parts. In this study, the monitoring data of electrical signals and arc morphology during the WAAM process of 2319 aluminum alloy were investigated using a high-speed camera system and current/voltage acquisition system. By analyzing the current and voltage signals, as well as the arc imaging results, the influence of arc stability on the forming of the cladding layer was studied. The experimental results indicated that when both current and voltage exhibit regular periodic fluctuations, this manifests as a stable short-circuit droplet transition form, while sudden changes in these signals represent abnormal droplet transition forms. The adaptability of the process directly influenced the arc shape, thereby affecting the forming of the cladding layer. Under the process parameters of welding speed of 240 cm/min and wire feeding speed of 6.5 m/min, it was observed that the current signal exhibited a tight state and the variance of the arc width was minimized. This indicated that at a higher wire feeding speed, the droplet transfer frequency was increased. Under these process parameters, the arc output was more stable, resulting in a uniform metal coating. [ABSTRACT FROM AUTHOR]

• ALD is a versatile method for creating functional barriers for primary packaging materials. • ALD metal oxide coatings prevented formation of extractables and leachables as analyzed by hydrolytic resistance, water conductivity and ICP-OES in standard test conditions. • Functionality, such as transparent protection from UV–Vis light or hydrophilicity/hydrophobicity, could be tailored by ALD films. Novel pharmaceuticals and drug delivery devices may require better performance from the packaging material e.g., in terms of extractables and leachables, and unwanted interactions. To address this, we applied atomic layer deposition (ALD) to build nanometer-range SiO 2 , ZrO 2 and Al 2 O 3 -TiO 2 films on primary packaging glass. Controlled modification of the surface also enabled creation of functionality without affecting visual appearance of the material. ALD-coated Type I borosilicate vials were compared to uncoated ones, and tailored functionality was presented by appropriate measurements. The tested ALD coatings formed a barrier on glass against extractables and leachables, from the vial and the coating alike. A good ALD coating prevents any leakage into the stored drug product. Hydrolytic resistance results improved by 85–92 %, and these results correlated well with straightforward water conductivity measurements. Opposite to uncoated borosilicate glass vials, no extracted elements could be detected from the extracts of the coated vials with stable ALD films. Improved surface integrity was observed with electron microscopy as well. ALD films increased hydrophilicity of the surface and tuning the ALD film thickness and composition allowed precise blocking of UV light wavelengths, without affecting transparency. As a conclusion, ALD is a versatile method to create barrier and functional films on primary packaging materials. [ABSTRACT FROM AUTHOR]

Polychlorotrifluoroethylene is used as a coating material over metallic seals in low-temperature applications to arrest fluid leakage from the impeller side in turbopumps. Typically, polychlorotrifluoroethylene coating is applied on V-type seals, with a thickness ranging from 80 to 130 μm by spraying an emulsion over the substrate followed by heat treatment. An attempt has been made to measure the polychlorotrifluoroethylene coating thickness over V-type seals using terahertz time-domain spectroscopy in reflection geometry, a noncontact, non-invasive NDT method. When the terahertz pulse from a transmitter photo-conductive antenna is incident on the V-type seal, it penetrates through the polychlorotrifluoroethylene coating. It gets reflected from the coating/base coat interface. Here, the reflected echoes from the air-to-polychlorotrifluoroethylene coating interface and polychlorotrifluoroethylene coating to the basecoat interface get overlapped in the time domain as the polychlorotrifluoroethylene coating layer is very thin. The sparse deconvolution technique separates the individual reflected signals and obtains the time delay signals from various interfaces. From the estimation of time delay values, the thickness of the coating has been computed using the refractive index value extracted using terahertz time-domain spectroscopy in transmission mode before the reflection measurements. The obtained thickness values are in close agreement with the coating thickness measured using optical microscopy. [ABSTRACT FROM AUTHOR]

This research helps with the creation, assessment, and characterization of a new hybrid protective coating for carbon steel alloy in acid conditions. The findings of this study will be useful for both chemical and petrochemical companies as well as scientists. This study aims to protect C-steel in acid pickling solution 1.0M HCl and formulate new hydrophobic protective hybrid organic–inorganic coatings from biopolymers chitosan and plant resin guar gum. Eight coating samples of chitosan in the absence and the presence of guar gum, silica and two heterocyclic compounds are prepared at feasible operational conditions using hot melt method. The aiding additives improved compatibility between coating constituents as confirmed by using different methods of analysis. This new processing approach has addressed the problems of using chitosan in corrosion control such as solubility in acid media and low mechanical strength. Coating samples of chitosan and its composites with the heterocyclic compounds (2-Hydrazinyl-6-methyl-4, 5-dihydro pyrimidine-4-on) or (2-Hydrazinyl-6-phenyl-4, 5-dihydro pyrimidine-4-on) are potent biocides. Coating shifts corrosion potential of carbon steel by 30 mV to more noble direction relative to the active potential 520 mV of bare carbon steel surface. Impedance and polarization measurements indicate that coating samples protect metal surface as mixed-type inhibitor by adsorption mechanism. There is a good agreement between percentages protection %P of coating calculated using the values of charge transfer resistance, Rct, and corrosion current density, icorr. All %P values are above 99% for all coating samples. Guar gum plant resin increases gloss of the coating film. Silica fills the pores in the polymeric film and increases the stuffiness of the polymeric coating film by modifying the particle size. All coated samples have high contact angle ranging from 150° to 165° indicating low wettability and high hydrophobicity of coating film on the metal surface. [ABSTRACT FROM AUTHOR]

Since precision engraving is essential for almost any product or application, it is important that the printing system produces smooth and clear prints. In this regard, the rollers are made of steel and polymeric materials. However, light cylinder production is economical, transportation costs are very low, and it provides ease of transportation and distribution for printing houses. However, regional chain orientations and cracks occur in the polymeric material on the conical surfaces of the cylinders with shafts longer than 1 m. Therefore, it is necessary to improve the surface properties of polymeric cylinder. In this study, electrolytic hard chromium (Cr) and soft copper (Cu) metal layers, conductive (Ni and Ag) paint and polyester coating were successfully fabricated on polymeric lightweight cylinders via electroplating, spraying and hand brushing techniques for photogravure press application. At the fabrication stage on the steel base cylinders, polyurethane has been molded by using an injection molding machine. In order to eliminate the porosities, where polyurethane takes place, polyester has been coated on the polymeric cylinder and consequently polyester has been painted with conductive dye to obtain the conductivity. Then Cu and Cr have been coated by using the electroplating method and gravured. At the end of final stage, the process has been completed with coating of Cr on the Cu layer/conductive paint/polyester coating/polyurethane substrate. Phase analysis, microstructures and mechanical properties of the obtained samples have been examined through XRD, SEM–EDS, surface roughness, microhardness, tensile, three-point bending, scratch and wear machines. As a remarkable result of these studies, correlations were established between the quality of the layers and the mechanical properties as innovative scientific approaches, and between the layers produced on an experimental basis and the samples produced on a fabrication basis, they were produced and used in high-quality multilayered architecture to engraving technology and then to the society because of its effectiveness. [ABSTRACT FROM AUTHOR]

Magnetised zeolite A, zeolite X and Na, K-CHA composites with superparamagnetic nanoparticles of SiO2-coated Fe3O4 or CoFe2O4 ferrite spinels were prepared, characterised and tested for ion exchange efficacy. They were synthesised by following three steps, synthesising Fe3O4 and CoFe2O4 nanoparticles by a solvothermal method, coating the metal oxide particles with SiO2 by a sol-gel process, and attaching the MxOy/SiO2 onto the zeolites during synthesis. The magnetic zeolites were characterised by X-ray diffraction, X-ray fluorescence spectroscopy, Raman spectroscopy, vibrating sample magnetometry and both scanning and transmission electron microscopy. It was confirmed they had superparamagnetic properties due to successful attachment of the MxOy/SiO2 particles onto the zeolites. Adsorption capacities of Sr2+ onto the magnetic zeolite A and zeolite X and Cs+ onto the magnetic Na,K-CHA were also evaluated. The results show theMxOy/SiO2 did not block the adsorption sites of the zeolites and the MxOy/SiO2 particles were not detached from the zeolites during the adsorption experiments. [ABSTRACT FROM AUTHOR]

The properties of protective coatings made from organic coatings on metallic substrates strongly depend on the condition of the substrate surface. This refers to the condition of the edges, welds, and the surface in general. Edge treatment is one of the most important operations prior to the actual coating application. The coating's protective properties and its susceptibility to mechanical damage are directly affected by the edge treatment. The article deals with the problem of edge treatment of the base material and the effect of this treatment on the quality of surface finishing. The edges were modified in three ways on the prepared Kosmalt E 300 T samples. Subsequently, some samples were hot-dip galvanized. An organic coating was then applied as the final surface treatment to all samples. The evaluation of the quality of the surface finishing was carried out on the above-mentioned, differently treated edges. The results strongly indicate the importance of the condition of the substrate surface and its influence on the quality of the final surface finish. [ABSTRACT FROM AUTHOR]

Metallic stainless steel bone implants are widely used due to their excellent mechanical properties, low cost, and ease of fabrication. Nanofibrous composite polymers have been proposed as coatings to promote biocompatibility and osseointegration, thanks to their biomimetic morphology that resembles the extracellular matrix. However, critical practical issues are often overlooked in the literature. For instance, applying coatings to implants with different shapes presents a significant technological challenge, as does evaluating viable sterilization procedures for hybrid devices containing electrospun polymers. In addition, infections pose a risk in any surgical procedure and can lead to implant failure, there is a need for antimicrobial prevention during surgery as well as in the short term afterward. In this work, we propose a new and straightforward method for manufacturing nanofibrous composite coatings directly on thin cylindrical-shaped metallic implants. Poly(ε-caprolactone) (PCL) nanofibers containing bioactive glass microparticles were electrospun onto stainless steel wires and then post-treated using two different strategies to achieve both hydrophilicity and surface disinfection. To address antimicrobial properties, amoxicillin-loaded Eudragit®E nanofibers were co-electrospun to impart pH-selective release behavior in event of a potential infection. The resulting composite hybrid coatings were characterized morphologically, physically, chemically, and electrochemically. The antibacterial behavior was evaluated at different media, confirming the release of the antibiotic in the pH range where infection is likely to occur. The impact of this study lies in its potential to significantly enhance the safety and efficacy of orthopedic implants by offering a novel, adaptable solution to combat infection. By integrating a pH-responsive drug delivery system with antimicrobial coatings, this approach not only provides a preventive measure during and after surgery but also addresses the growing issue of antibiotic resistance by targeting specific infection conditions. [ABSTRACT FROM AUTHOR]

Corrosion and biofouling are wetting‐related phenomena that limit the effective use of metals in aqueous media. Nonwettable surfaces can mitigate the adverse effects of wetting by minimizing contact with water. However, current achievements in this field fall short of meeting industrial requirements due to the short lifetime of plastrons. This study proposes a method to measure the protective sustainability of plastron. Superhydrophobic (SHS) and aerophilic (APhS) surfaces are constructed on lightweight aluminum and are initially analyzed by conventional goniometry, which show comparable values. However, the plastron that develops underwater is substantially different. While SHS exhibit unevenly broken plastron, APhS show uniform, continuous plastron. As an example of the sustained protective performance of plastron, the corrosion resistance of SHS and APhS is presented. Potentiodynamic polarization, impedance spectroscopy, and long‐term immersion in seawater show a drastic enhancement in corrosion resistance, exclusively for APhS. In fact, almost no electrochemical signals are measurable, and no pitting corrosion is observed after 415 days of immersion in seawater. Conversely, SHS show no noticeable improvement and corrode faster than bare Al due to plastron loss. Since goniometric measurements do not provide information on plastron, it is essential to analyze the plastron for any non‐wettable surface utilized underwater. [ABSTRACT FROM AUTHOR]

There is tremendous interest in the development of highly wear‐resistant coatings for metallic materials to reduce energy loss and prolong service life. In this study, the authors propose an approach to develop nanocomposite coatings featuring deformable nanocrystals embedded in amorphous matrix for self‐lubrication and superior wear resistance. The dual‐layered nanocomposite coatings are prepared by plasma electrolytic oxidation (PEO) on a Ti‐Nb‐Ta‐Zr‐Hf (TNZTH) refractory multi‐principal element alloy (RMPEA) and commercially pure Ti (cpTi). The inner layers of PEO coatings are composed of substrate element oxides (amorphous TNZTH─O oxide or anatase TiO2), while their outer layers exhibit typical nanocomposite structures. Different from the cpTi‐based PEO coating outer layers composed of brittle rutile TiO2 nanoparticles dispersed in an amorphous matrix of SiO2 and Na2O·nSiO2, the outer layers of TNZTH‐based PEO coatings are featured by deformable Na2Zr(Hf)O3 nanocrystals heterogeneously embedded in an inhomogeneous amorphous matrix composed of TNZTH─O oxide, SiO2, and Na2O·nSiO2. As a result, the TNZTH‐based PEO coatings exhibit favorable self‐lubricating performance and superior wear resistance, while the cpTi‐based PEO coatings are completely destroyed after sliding wear. Thus, this study offers valuable insights into the design and development of self‐lubricating coatings with superior wear resistance for metallic materials. [ABSTRACT FROM AUTHOR]

Proton exchange membrane water electrolyzers (PEMWE) are being considered as a high efficiency potential option for green hydrogen production. Bipolar plates (BPPs) are a crucial element within PEMWEs serving a significant function in the sepration of product gases, distribution of flow field, electron collection, and heat conduction. This review paper aims to investigate recent research on materials used in BPPs and examine several corrosion prevention strategies aimed at enhancing their durability and performance in PEMWEs. It presents a thorough examination of the materials utilized in BPPs, encompassing both conventional metals and advanced coatings. The analysis focuses on elucidating the distinct advantages and limits associated with these materials in relation to conductivity, mechanical strength, and resistance to corrosion. The review examines electrochemical techniques and microscopy methods utilized to assess corrosion behavior, guiding the selection and optimization of materials. Ultimately, this review offers a thorough comprehension of the current advancements in BPP materials and corrosion protection strategies for PEMWEs. [Display omitted] • Consolidating recent research on BPP materials and corrosion prevention in PEMWEs. • Examining BPP materials, including traditional metals and advanced coatings. • Elucidating strengths and weaknesses of materials in conductivity and corrosion. • Investigating the physical and electrochemical characterization techniques. [ABSTRACT FROM AUTHOR]

Ceramic coating is a well-established method for enhancing the wear and corrosion resistance of metal components. Al 2 O 3 coating has been extensively utilized in industrial applications. However, existing ceramic coating processes often yield coatings that are relatively thin with limited wear and corrosion resistance. Furthermore, achieving efficient and high-quality coatings on complex metal surfaces poses significant challenges. The poor wettability between ceramics and metals further complicates the bonding at their interface. Chromium (Cr), a commonly used alloying element in steel, exhibits excellent interfacial wettability with iron (Fe), making it an ideal transition material for the Al 2 O 3 /Fe interface. In this study, complex Al 2 O 3 -based ceramic shells were fabricated via Binder Jetting. The Cr coating was coated on the surface of the shell, and then the Fe-based metal liquid was poured into the Al 2 O 3 -based ceramic shell to achieve metallurgical bonding at the Al 2 O 3 /Fe interface by temperature control treatment. The performance of the Al 2 O 3 ceramic matrix and the microstructure of the Al 2 O 3 /Fe interface with the Cr intermediate transition layer were investigated. The results indicate that when the solid loading of the Cr coating is 60 wt%, a uniform, and stable Cr coating can be formed on the surface of the sintered Al 2 O 3 -based ceramic. The bending strength of the Al 2 O 3 -based ceramic matrix increased from 113.79 MPa to 134.69 MPa. The Cr coating significantly improved the wettability between the Al 2 O 3 -based ceramic and the Fe-based metal, reducing the wetting angle from 98.9° to 78.4°. The interface between the Al 2 O 3 -based ceramic and Fe-based metal formed FeCr 2 O 4 after infusion, resulting in a well-bonded interface without significant cracks. [ABSTRACT FROM AUTHOR]

Hemispherical resonator gyroscope is a type of solid-state gyroscope, in which the fused silica hemispherical resonator with a high-quality factor (Q factor) is the key for the fabrication of high-performance devices. However, the metal film coated on the silica as the electrode for trigging the resonance often leads to the largely deteriorated Q factor. In this work, high-quality graphene films with controllable number of layers are uniformly coated on silica utilizing C2H4 as precursor in chemical vapor deposition. Replacing the metal film as the electrode, the hemispherical resonator coated with graphene demonstrates a Q factor of 3.38 × 106, with a high retention of 77.17%. At an optimized preparation temperature of 1130 °C, the graphene film shows a good adhesion with the silica hemisphere, providing an excellent candidate as the electrode for high-performance hemispherical resonators. [ABSTRACT FROM AUTHOR]

Purpose: Nanoparticles (NPs) as radiosensitizers present a promising strategy for enhancing radiotherapy effectiveness, but their potential is significantly influenced by the properties of their surface coating, which can impact treatment outcomes. Most Monte Carlo studies have focused on metallic NPs without considering the impact of coating layers on radiosensitization. In this study, we aim to assess both the physical and radiobiological effects of nanoparticle coatings in nanoparticle-based radiation therapy. Materials and methods: In this simulation study, we used Geant4 Monte Carlo (MC) toolkit (v10.07.p02) and simulated the bismuth, gold, iridium and gadolinium NPs coated with polyethylene glycol (PEG-400: Density: 1.13 g/cm³, Molar mass: 380–420 g/mol) as radiosensitizer for photon beams of 30, 60 and 100 keV. Secondary electron number and reactive oxygen species enhancement factor were estimated. Also, dose enhancement factor (DEF) was determined in spherical shells with logarithmic scale thickness from the nanoparticle surface to 4 mm. Results: Secondary electron emission was highest at 30 keV for gold, bismuth, and iridium NPs, while gadolinium NPs peaked at 60 keV. Coating reduced electron emissions across all energies, with thicker coatings leading to a more significant decrease. DEF values declined with increasing radial distance from the NP surface and were lower with thicker coatings. For gadolinium NPs, DEF behavior differed due to K-edge energy effects. Reactive species generation varied, showing maximum production at 30 keV for gold, bismuth, and iridium NPs, while gadolinium NPs showed peak activity at 60 keV. PEG coatings enhanced reactive species formation at 100 keV. Conclusion: The findings indicate that the coating layer thickness and material not only influence the emission of secondary particles and DEF but also affect the generation of reactive species from water radiolysis. Specifically, thicker coatings reduce secondary particle emission and DEF, while PEG coatings demonstrate a dual behavior, offering both protective and enhancing effects depending on photon energy. These insights underscore the importance of optimizing NP design and coating in future studies to maximize therapeutic efficacy in nanoparticle-based radiation therapy. [ABSTRACT FROM AUTHOR]

LiCoO2 (LCO) has been the cathode material of choice for three decades for durable, lightweight Li‐ion storage systems. Being charged up to 4.2 V versus Li/Li+, LCO provides excellent cycling stability with a specific capacity of ≈140 mAh g−1. Raising the cut‐off voltage to 4.6 V improves capacity by up to 60% however, it leads to rapid degradation of the cathode structure. Here, a one‐pot dual coating of MgF2 and AlF3 with fluorinated electrolyte additives achieves 190 mAh g−1 at a 0.5 C rate after 400 cycles with a capacity retention of 93%. Various analytical tools are used to follow the structural and morphological changes during cycling. Synergistically, ion transport is improved, and detrimental interfacial side reactions with the electrolyte solutions are fully mitigated. Structural stability is thus improved by using this coating, with only a little loss of the active material. This work provides a brief guideline for designing dual metal‐ion‐based surface coatings in various electrolytes to develop high‐voltage cathode systems for Li and maybe also Na batteries. [ABSTRACT FROM AUTHOR]

Magnetised zeolite A, zeolite X and Na,K-CHA composites with superparamagnetic nanoparticles of SiO2-coated Fe3O4 or CoFe2O4 ferrite spinels were prepared, characterised and tested for ion exchange efficacy. They were synthesised by following three steps, synthesising Fe3O4 and CoFe2O4 nanoparticles by a solvothermal method, coating the metal oxide particles with SiO2 by a sol-gel process, and attaching the MxOy/SiO2 onto the zeolites during synthesis. The magnetic zeolites were characterised by X-ray diffraction, X-ray fluorescence spectroscopy, Raman spectroscopy, vibrating sample magnetometry and both scanning and transmission electron microscopy. It was confirmed they had superparamagnetic properties due to successful attachment of the MxOy/SiO2 particles onto the zeolites. Adsorption capacities of Sr2+ onto the magnetic zeolite A and zeolite X and Cs+ onto the magnetic Na,K-CHA were also evaluated. The results show the MxOy/SiO2 did not block the adsorption sites of the zeolites and the MxOy/SiO2 particles were not detached from the zeolites during the adsorption experiments. [ABSTRACT FROM AUTHOR]

Electrolyte additives have been promising strategies aimed at lithium metal dendrite growth and active materials loss of sulfur cathode those have troubled the development of Li‐S batteries (LSBs), while current interface modulations of electrodes are still challenged by low protection efficiency and high N/P ratio. Herein, potassium 3‐thiophenetrifluoroborate (KPTB) is adopted as an additive to construct versatile interface for both lithium metal anode (LMA) and sulfur cathode. The preferentially electrochemical reduction and oxidation of PTB (3‐thiophenetrifluoroborate) moiety, as well as electrostatic shielding exerted by K+ ion, enable F‐rich solid electrolyte interphase for LMA and construct polythiophene based protection layers on the two electrodes, facilitating fast and uniform ion/electron transfer across the interface, suppressing polysulfide outflow and maintaining integrity of electrodes. Electrochemical measurements indicate that optimized dosage of KPTB in electrolyte remarkably enhances reversibility and cyclic stability of the two electrodes, and endows LSBs with excellent performances over wide temperature range (−25–50 °C). Remarkably, the Li‐S full cells using a 75 µm of LMA can deliver a capacity of 6.0 mAh cm−2 and excellent cyclic performances for 350 cycles, at a N/P ratio as low as 1.4. This work can provide new reliable solution for electrolyte additive based interface protections in LSBs. [ABSTRACT FROM AUTHOR]

In this study, a copper brazing filler metal coating is fabricated on a 304 stainless steel (304SS) substrate using an electroplating technique. The effect of using electroplated copper brazing filler metal coatings compared to pure copper foil of the same thickness for vacuum brazing of stainless steel joints is investigated. The microstructure and microhardness of the brazed joints are characterized using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and a Vickers hardness tester. The shear strength of the brazed joints is measured using an INSTRON 5869 universal testing machine. The results indicate that the electroplated Cu coating is dense, predominantly with a single cubic phase, with a few copper particles aggregating on the surface. Under electroplating conditions of 20 mA cm−2 for 1 h, the coating thickness was 56 μm. The shear strength of the brazed joint with this coating reached a maximum of 333.7 MPa, which is higher than that of a brazed joint with a 60 μm thick copper foil, which exhibits a shear strength of 303.2 MPa. The shear strength of the brazed joints shows an initial increase followed by a decrease as current density and electroplating time increase. This study provides significant technical support for brazing complex shapes or precision components. It suggests a method to simplify the brazing process, reduce production costs, and enhance the strength of brazed joints. [ABSTRACT FROM AUTHOR]

The use of supported metal-based heterogeneous catalysts is very ubiquitous in the modern chemical industry. Although high reactivity has been achieved, conventional supported metal-based heterogeneous catalysts commonly face the problem of rapid deactivation, generally involving leaching, poisoning or sintering of the active metal species, which is particularly serious in various solid acid catalysis processes. To overcome these drawbacks, different strategies have been adopted, including strengthening metal–support interactions, confining metal species in various porous materials, or coating the active metal nanoparticles with thin shells, which may generate effective metal-based nanocomposite catalysts with enhanced stability. In this feature article, we summarize our recent work on the design of some metal-based nanocomposites possessing yolk–shell, core–shell or other confined structures for enhanced catalytic applications in several important acid catalysis reactions, such as cycloaddition of CO2, epoxidation of olefins, acylation of aromatic compounds, and transesterification/carbonylation synthesis of organic carbonates. More attention is paid to the design and preparation strategy of metal-based nanocomposite catalysts, which can generate unique catalytically active and stable metal sites for meeting the tough requirements of a specific catalytic reaction. Finally, the existing challenges and the future directions for metal-based nanocomposite catalysts with respect to the preparation strategies and catalytic application prospects are proposed. [ABSTRACT FROM AUTHOR]

Magnesium alloys have great potential for industrial and aerospace applications due to their low density and high strength. Aiming at its defects of poor corrosion resistance and susceptibility to galvanic coupling corrosion in metal coatings, a composite coating was prepared on the surface of AZ91D magnesium alloy by the hydrothermal method. Scanning electron microscope, x-ray diffraction, and x-ray photoelectron spectroscopy were used to characterize the surface micromorphology, phase composition, and elemental valence and evaluate the adhesion of the coating to the substrate by the ASTM D3359-09 test standard. Electrochemical experiments were done in a 3.5% NaCl solution. The results show that there are nanoscale dense granular structures on the surface of the samples, and the main components of the coatings are Mg(OH)2, Al2O3, and MgSiO3. ASTM grade 4B is between coating and substrate. The corrosion rate of the best sample was reduced by a factor of 238.96 compared to the substrate, and the corrosion current density was reduced by two orders of magnitude. The corrosion rate and corrosion current of the samples after repeated friction did not change much compared with those before friction, which proved that the composite coating had better corrosion resistance and friction stability. [ABSTRACT FROM AUTHOR]

Through a simple solution method, TiO(Acac)2 was used to in-situ coat the all-inorganic perovskite material CsPbBr3. After heating at 400 ℃, CsPbBr3 @ TiO2 core-shell structure microcrystals were directly prepared. The crystal structure, microscopic morphology, and chemical composition of CsPbBr3 @ TiO2 microcrystals were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS). It was confirmed that the in-situ metal oxide coating on the perovskite formed welldispersed spherical shell structures with sizes of 4 ~ 8 μm. A CsPbBr3 @ TiO2 thin film gas sensor was constructed on a fluorine-doped tin oxide (FTO) electrode using spin-coating method. The sensitivity of the sensor to H2 S gas was tested at room temperature. The results show that the sensor has a detection limit of 25 ppb (1 ppb = 10 -9) for H2 S gas, with a response and recovery time of 24/21 s to 100 ppb H2 S, and a sensitivity of 0. 59. The response curve exhibits good cyclic stability. Moreover, the sensor maintains over 90% stability within 30 d of exposure in air and possesses excellent gas selectivity and humidity resistance. Photoluminescence (PL) spectroscopy, time-resolved photoluminescence (TRPL) spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis), and ultraviolet photoelectron spectroscopy (UPS) were employed to analyze the band positions, charge dynamics, and coordination mechanisms. The sensing mechanism was elucidated using the oxygen adsorption principle. This work provides a new approach for the stable monitoring of low concentrations of H2 S gas at room temperature. [ABSTRACT FROM AUTHOR]

Manganese (Mn) is an essential trace mineral for brain function, but excessive accumulation can cause irreversible nervous system damage, highlighting the need for proper Mn balance. ZIP14, ZnT10, and ZIP8 are key transporters involved in maintaining Mn homeostasis, particularly in the absorption and excretion of Mn in the intestine and liver. However, their roles in the brain are less understood. The blood–cerebrospinal fluid barrier and the blood–brain barrier, formed by the choroid plexus and brain blood vessels, respectively, are critical for brain protection and brain metal homeostasis. This study identified ZIP14 on the choroid plexus epithelium, and ZIP8 and ZnT10 in brain microvascular tissue. We show that despite significant Mn accumulation in the CSF of Znt10 knockout mice, ZIP14 expression levels in the blood–cerebrospinal fluid barrier remain unchanged, indicating that ZIP14 does not have a compensatory mechanism for regulating Mn uptake in the brain in vivo. Additionally, Mn still enters the CSF without ZIP14 when systemic levels rise. This indicates that alternative transport mechanisms or compensatory pathways ensure Mn balance in the CSF, shedding light on potential strategies for managing Mn-related disorders. [ABSTRACT FROM AUTHOR]

Stainless steels 316 and 304 are among the alloys commonly used to make medical equipment, including surgical instruments. These steels, however, do not exhibit properties that control bacterial growth or destroy bacteria upon contact, leading to significant contamination. This problem can be largely mitigated by applying coatings with high antibacterial properties. One such coating that has attracted considerable attention from researchers, in recent years, is Zr-based metallic glass coatings. In this study, after studying the effects of different elements on the antibacterial behavior of coatings, an alloy with the chemical composition of Zr30Cu20Al10Ag10Cr10Si10B10 was designed and produced. A thin layer of this amorphous alloy was then applied to a 316 stainless steel substrate, and its behavior against two common hospital bacteria was studied. After weighing and mixing the selected elements in the required stoichiometric ratios and homogenizing them using a mechanical ball mill, a target with the desired chemical composition was produced using Spark Plasma Sintering (SPS). Structural investigations revealed a uniform distribution of the elements in the produced target. Using this target, thin layers of the alloy with different thicknesses were deposited on the 316 stainless steel substrate. Preliminary investigations showed that the coatings, in addition to forming a good bond with the substrate, possess a glassy and amorphous structure. The antibacterial behavior of the coatings against Escherichia Coli and Staphylococcus Aureus was then investigated. The results showed that the coatings, due to the presence of copper and silver, exhibit high antibacterial properties against these bacteria. Furthermore, the application of the coating, which reduces the roughness of the polished 316 substrate by 50%, can significantly affect the adhesion of human and animal blood platelets, as well as human and animal cancer cells, to surgical instruments made from 316 stainless steel. [ABSTRACT FROM AUTHOR]

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Phytic acid as an efficient, green and renewable bio-based flame retardant. However, in view of the large number of toxic fumes generated during combustion and the easy loss of flame retardants, to tackle these issues, the current study employed a straightforward two-step process to generate phytate metal salt wood composites (PAN-M, M = Mg, Cu, Fe, Ai and Ni) in cell walls. Compared with natural wood (Control), PAN-M has good leaching resistance of 15~50%, lower hygroscopicity of 15~30% and improved mechanical strength. The total heat release and smoke emission of PAN-Cu are reduced by 34.54% and 83.05% respectively, the LOI of PAN-Cu is increased by 117%, the smoke density SDR is only 8.38 and the weight gain is 16.9%. This is mainly due to the apparent surface coke protection of metal phytates and catalytic graphitisation of solid residues by metal ions. The improved carbon layer plays an effective insulating role, limiting flue gas emissions, flame retardant loss and water contact. In addition, results show that PAN-Cu can significantly enhance the dehydration effect of carbon compared to other metal ions. Therefore, PAN-M is an efficient, green and sustainable flame retardant for wood. [ABSTRACT FROM AUTHOR]

This comprehensive work addresses the pressing environmental concerns associated with the automotive industry's expansion and its reliance on fossil fuels. Focusing on the pivotal role of energy in vehicle propulsion, the paper explores diverse energy utilization methods and their conversion into mechanical energy for mobility. While chemical energy currently powers most vehicles, it contributes to detrimental emissions, necessitating innovations to enhance fuel quality, engine design, and materials. The research emphasizes refining the performance, and life cycle, and minimizing exhaust emissions of internal combustion engines. A key focus of this paper is the proposal of a novel approach that advocates the application of coatings to the combustion surface and catalytic converter to bolster engine performance and curtail emissions. The researchers highlight the efficacy of metal coatings, including thermal barrier coatings and catalytic coatings, presenting a comprehensive overview of experimental research articles endorsing the positive impact of metal coating strategies. These coatings aim to enhance combustion dynamics, manage thermal stresses, and optimize catalytic converter efficiency. In this technical paper offers valuable insights for researchers and engineers committed to mitigating the environmental impact of the automotive industry. It underscores the critical need for optimizing engine performance and minimizing emissions, with a specific emphasis on the promising potential of metal coating technologies to significantly contribute to these overarching objectives. [ABSTRACT FROM AUTHOR]

Grit particles remaining on the substrate surface after grit blasting are generally considered to impair the thermal performance of thermal barrier coatings (TBCs). However, the specific mechanisms by which these particles degrade the multilayer structure of TBCs during thermal cycling have not yet been fully elucidated. In this study, the superalloy substrate was grit-blasted using various processing parameters, followed by the deposition of thermal barrier coatings (TBCs) consisting of a metallic bond coat (BC) and a ceramic top coat (TC). After thermal shock tests, local thinning or discontinuities in the thermally grown oxide (TGO) layer were observed in TBCs where large grit particles were embedded at the BC/substrate interface. Moreover, cracks originated at the concave positions of the TGO layer and propagated vertically towards BC; these cracks may be associated with additional stress imposed by the foreign grit particles during thermal cycling. At the BC/substrate interface, crack origins were observed in the vicinity of large grit particles (~50 μm). [ABSTRACT FROM AUTHOR]

The fire risk rating assessment of wood was evaluated using fire performance index-VIII, fire growth index-VIII, and fire risk index-IX from previously described Chung's equations. The burning properties of the materials was measured using a cone calorimeter (ISO 5660-1). SnO, SnO2, FeO and Fe2O3 were used as the metal oxides, and sodium silicate was mixed to increase the flame-retardant effect. The fire performance index-VIII was 15.5–139.3 times higher than the uncoated specimen. The fire growth index-VIII was 12–71 times lower than the uncoated specimen. The fire risk index-IX of the coated specimens was 239–9861 times lower than the uncoated specimens. SnOSS was the lowest risk material according to the fire risk rating FRI-IX. A lower oxidation state was a safer material for an initial fire than a higher oxidation state. All specimens showed an improved fire risk compared to uncoated specimens. [ABSTRACT FROM AUTHOR]

Liquid metal, as a novel material, has become ideal for the fabrication of flexible conductive fibers and has shown great potential in the field of biomedical sensing. This paper presents a comprehensive review of the unique properties of liquid metals such as gallium-based alloys, including their excellent electrical conductivity, mobility, and biocompatibility. These properties make liquid metals ideal for the fabrication of flexible and malleable biosensors. The article explores common preparation methods for liquid metal conductive fibers, such as internal liquid metal filling, surface printing with liquid metal, and liquid metal coating techniques, and their applications in health monitoring, neural interfaces, and wearable devices. By summarizing and analyzing the current research, this paper aims to reveal the current status and challenges of liquid metal conductive fibers in the field of biosensors and to look forward to their development in the future, which will provide valuable references and insights for researchers in the field of biomedical engineering. [ABSTRACT FROM AUTHOR]

Due to their excellent hardness, transition metal nitrides have become a promising coating material for cutting tools and high-friction surfaces. The wear and corrosion protection offered by metal nitride hard coatings has paved the way for research on different combinations of metal nitrides. In this study, binary transition metal nitride coatings of CrMoN and CrTiN are deposited onto cutting tools and different substrates by co-sputtering of two metal targets simultaneously at an oblique angle by an ion-assisted DC magnetron sputtering process. The purpose of the deposition is to develop a uniform adhesive hard coating onto the specimens and to study their characteristics and performance. Both the hard adhesive coatings developed offer good surface morphologies which have been confirmed by AFM and FESEM, and their elemental composition is confirmed by XRD, XPS, and EDS characterizations. Hardness is measured by nanoindentation and also electrochemical studies for corrosion measurements are performed. In both the coatings, individual nitride phases have been formed in a mixed manner and have achieved a hardness value of about 13 GPa and the corrosion resistance of the coated specimen is found to be improved in comparison with the uncoated substrates. [ABSTRACT FROM AUTHOR]

Significant adhesion forces (van der Waals, electrostatic, and capillary) exist at the nanoscale. Knowing the effective forces and influencing factors is crucial to reduce the adhesion force in microelectromechanical systems. In this paper, the effect of silver and gold metal coating in various thicknesses on silicon surfaces' adhesion force was investigated. Silver and gold metals with a thickness of 10, 120, and 500 nm were coated on the silicon substrate <100> by the magnetron sputtering method. Adhesion forces were obtained via Rabinovitch modeling and experimental method. Atomic force microscopy was used to experimentally obtain data on modeling methods. The findings show that coatings of both metals with various thicknesses reduce the adhesion force. Gold further reduced the surface adhesion as compared with the silver and gold coating. Therefore, gold can be a better option for the coating to reduce the adhesion force, especially in applications such as micro assembly. [ABSTRACT FROM AUTHOR]

In view of the importance of metal coatings, this study addresses the ion concentration of the anti‐corrosive coating's immersion solution. The physical properties of the coating surface, such as molecular characteristics, smoothness, and structural strength, were changed by adding nano‐SiO2 in the immersion solution to formulate the best scheme for anti‐corrosive performance. The composite coating was prepared on the surface of AZ31B magnesium alloy by electroless plating. Besides, the surface coating based on AZ31B substrate has high‐quality corrosion resistance to different types of contaminated media. The experimental results demonstrate that the nanocomposite coating can form an ultrafine particle‐filling effect on the metal surface, which is lower than the drag force of the conventional metal surface. Considering the slip velocity gradient in the contact coating area, we reduce the shear stress and drag force, verifying the nanocomposite coating's effect on reducing the reaction force. The contact angle of water droplets in the composite coating is greater than 158.7°. The study finally verifies that the prepared coating has good self‐cleaning potential which can prevent the corrosion of different polluted media. [ABSTRACT FROM AUTHOR]

This perspective points out the potential of solid‐state Na‐air/O2 batteries for powering next‐generation storage devices, highlighting their high energy density, efficiency, and cost‐effectiveness. The challenges faced by Na‐air/O2 batteries, including liquid electrolyte instability, O2/O2− crossover, Na anode passivation, and dendritic growth are addressed. Strategies such as exploring solid‐state electrolytes (SSE), mitigating O2/O2− crossover, protecting the Na anode, and enhancing the solid electrolyte interphase (SEI) are discussed as potential solutions. Future challenges in advancing the technology are reviewed, emphasizing the need for addressing and understanding the fundamental mechanisms of (quasi)solid‐state Na‐air/O2 batteries (i.e., discharge product chemistry, dendritic growth, O2 crossover, the electrolyte properties, the stabilization of battery chemistry and Na+ transport). A roadmap outlining future directions is presented to overcome these challenges, with the goal of fully harnessing the potential of Na‐air/O2 batteries as a viable option for renewable energy and industrial‐scale commercialization. [ABSTRACT FROM AUTHOR]

In situ vaccine (ISV) is a versatile and personalized local immunotherapeutic strategy. However, the compromised viability and function of dendritic cells (DCs) in a tumor microenvironment (TME) largely limit the therapeutic efficacy. We designed a hybrid nanoparticle-based ISV, which accomplished superior cancer immunotherapy via simultaneously scavenging reactive oxygen species (ROS) and activating the stimulator of interferon genes (STING) pathway in DCs. This ISV was constructed by encapsulating a chemodrug, SN38, into diselenide bond-bridged organosilica nanoparticles, followed by coating with a Mn2+-based metal phenolic network. We show that this ISV can activate the STING pathway through Mn2+ and SN38 comediated signaling and simultaneously scavenge preexisting H2O2 in the TME and Mn2+-catalyzed •OH by leveraging the antioxidant property of diselenide and polyphenol. This ISV effectively activated DCs and protected them from oxidative damage, leading to remarkable downstream T cell activation and systemic antitumor immunity. This work highlights a nanoparticle design that manipulates DCs in the TME for improving the ISV. [ABSTRACT FROM AUTHOR]

Ceramic protective coatings applied to metallic interconnects play a vital role in solid oxide cells (SOCs) preventing interconnect degradation. In this study, uniform, dense, and crack-free single-layer coatings of MnCo 2 O 4 , Mn 1.7 CuFe 0.3 O 4 , and dual-layer coatings of MnCo 2 O 4 /Mn 1.7 CuFe 0.3 O 4 spinel are deposited onto complex-shaped metallic interconnect using electrophoretic deposition (EPD) method. The porosity of sintered MnCo 2 O 4 and Mn 1.7 CuFe 0.3 O 4 coatings in reduction treatment (1000 °C for 2h in H 2), followed by subsequent oxidation treatment (900 °C for 2h in air) is approximately 50% less than that of these coatings sintered in oxidation treatment (900 °C for 4h in air). The results indicate that the thickness of the sintered MnCo 2 O 4 , Mn 1.7 CuFe 0.3 O 4 single-layer, and MnCo 2 O 4 /Mn 1.7 CuFe 0.3 O 4 dual-layer coatings in reduction + oxidation treatments is 46.2%, 28.2%, and 23.1% denser, respectively, compared to sintered in oxidation treatment. Raman spectroscopy and Energy Dispersive Spectroscopy (EDS) analysis showed that in sintered dual-layer coatings subjected to reduction treatment followed by a subsequent oxidation treatment, exhibit a much more efficient interdiffusion processes throughout the thickness of the coating yielding the formation of a mixed (Mn, Cu, Fe, Co) 3 O 4 spinel, comparing to dual-layer coatings undergoing only oxidation treatment. The dual-layer spinel coatings of MnCo 2 O 4 /Mn 1.7 CuFe 0.3 O 4 present promising candidate for protective coatings on metallic interconnects. • A uniform and crack-free coating applied onto complex-shaped interconnects using the EPD method. • MnCo 2 O 4 /Mn 1.7 CuFe 0.3 O 4 dual-layer coating is a promising candidate for protective coatings. • Dual-layer coating densification in reduction + oxidation is higher than oxidation treatments. • Dual-layer coating provides higher protection against Cr diffusion than single-layer coating. [ABSTRACT FROM AUTHOR]