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Poly[(n‐butyl methacrylate)‐co‐(n‐butyl acrylate)]‐based core‐shell latexes are prepared by emulsion polymerization with a shell copolymer glass transition temperature (Tg) of 5 °C, but differences in core copolymer wt.% (4–90) and Tg (5–25 °C), and in wt.% of diacetone acrylamide (DAAM) in the shell copolymer, which facilitates crosslinking in the percolating phase of films through addition of adipic acid dihydrazide. Analysis of samples removed from reactions, together with analysis of film cross‐sections by atomic force microscopy (AFM), confirms the core‐shell particle structures and honeycomb morphologies in films, with simultaneous AFM and infrared spectroscopy showing the distribution of hydrazone crosslinks. Increasing wt.% DAAM (i.e., degree of crosslinking) in the percolating phase shifts film tensile stress–strain curves towards higher stresses and lower extensions at break. For core and shell copolymer Tgs of 5 °C there is a small effect of core wt.%. At 70 and 80 wt.% core, increasing core copolymer Tg also shifts the curves towards higher stresses and lower extensions at break. Thus by combining effects of core copolymer wt.% and Tg with effects of wt.% DAAM in the shell through the soft–soft nanocomposite approach, it is possible to achieve a wide range of tensile deformation behavior in films that have quite similar overall copolymer compositions. [ABSTRACT FROM AUTHOR]

Polydopamine has the capacity to adhere to a large variety of materials and this property offers the possibility to bind nanoparticles to solid surfaces. In this work, magnetite nanoparticles were deposited on gold substrates coated with polydopamine films. The aim of this work was to investigate the effects of the composition and morphology of the PDA layers on the sticking of magnetite nanoparticles. The polydopamine coating of gold surfaces was achieved by the oxidation of alkaline solutions of dopamine with various reaction times. The length of the reaction time to form PDA was expected to influence the composition and surface roughness of the PDA films. Magnetite nanoparticles were deposited on these polydopamine films by immersing the samples in aqueous dispersions of nanoparticles. The morphology at the nanometric scale and the composition of the surfaces before and after the deposition of magnetite nanoparticles were investigated by means of AFM and XPS. We found that the amount of magnetite nanoparticles on the surface did not vary monotonically with the reaction time of PDA formation, but it was at the minimum after 20 min of reaction. This behavior may be attributed to changes in the chemical composition of the coating layer with reaction time. [ABSTRACT FROM AUTHOR]

Polymer coatings have gained a lot of attention in the recent past because of their ability to be easily coated on complex shapes, their low cost, and their ability to reduce friction as compared to other materials. Polyether ether ketone (PEEK) is one such high-performance polymer that has gained significant attention in recent years due to its exceptional mechanical properties, chemical resistance, and thermal stability making it a prominent candidate for applications in industries. However, PEEK in its pristine form exhibits poor wear resistance with a moderate coefficient of friction (0.30–0.38). Many attempts have been made by several researchers to improve its wear resistance and lower the COF by developing composite coatings. Hence, in this review, we aim to summarize and present in detail the tribological evaluation of pristine PEEK and PEEK composite coatings by discussing the various methods adopted by the researchers to improve the properties of PEEK, the different types of reinforcements and various dispersion techniques used to develop PEEK composite coatings. By consolidating and analyzing the existing body of knowledge, we also aim to offer valuable insights into the development of more durable, high-performance PEEK nanocomposite coatings for a broad range of tribological applications. [ABSTRACT FROM AUTHOR]

Today, the production of edible and biodegradable films is one of the growing technologies in advanced societies. The use of these coatings is due to the replacement with polymeric materials and increasing the storage time of food. The main purpose of this study was to produce an edible film of soybeans protein isolate (3 to 7%), glycerol (1 to 3%) and Ziziphorpa capitata essential oil (0 to 1%) in order to create better taste and antimicrobial properties. After preparing the film, the physicochemical and mechanical properties of the film (thickness, density, solubility in water and acid, water vapor permeability, transparency, color changes, elongation percentage and tensile strength) were evaluated. After performing the above tests and investigating the effects of independent variables on the dependent variables, the oral film formulation was optimized. The results showed that the optimal formula can be achieved by using 3.54% soy protein isolate, 1% glycerol and 1% cactus essential oil at the level of desirability of 0.624. [ABSTRACT FROM AUTHOR]

Advancements in the synthesis of sulfur‐rich materials are driving progress across diverse fields owing to the rich and tunable functionalities of those materials. These materials are typically valued for their electrochemical behaviors, high refractive indices, heavy metal affinity, and ability to form dynamic covalent bonding. As a result, their applications span various industries including electronics, catalysis, lithium‐sulfur batteries, water reclamation, and optoelectronics. Moreover, elemental sulfur, a byproduct of the petroleum industry, is produced abundantly, necessitating the exploration of novel valorization routes for polymers made from this feedstock. The unique combination of properties of sulfur‐rich polymers also makes them an ideal platform for the development of high‐performance functional coatings, offering durability and tailored functionalities for protective coatings, thus enhancing materials lifespan and performances in a variety of environmental conditions. The presence of dynamic covalent bonds in many sulfur‐rich polymers enables the creation of self‐healing coatings, while sulfur itself or the comonomers can contribute to antimicrobial, antifouling, and corrosion‐resistant properties. Furthermore, sulfur‐rich polymers have the potential to be used in the design of icephobic and superhydrophobic coatings. This underscores the versatility of sulfur‐rich polymers as a platform for the creation of advanced coatings with superior properties. [ABSTRACT FROM AUTHOR]

Ceramic coatings have much potential for steel tubulars' protection against high temperature corrosion of gases and liquids, often containing abrasive solid particles, and to enhance their integrity in severe power generation, mineral and oil & gas production environments. Combining self-propagating high-temperature synthesis (SHS) with high-speed centrifugal process, alumina-based coatings were produced onto the inner surface of tubulars for these applications. According to the developed SHS batch formulation and the designed centrifugal device and process, well-consolidated composite ceramic layers with a thickness of 1.5–3 mm have been obtained. The developed SHS process does not create hazardous gases, and it takes ∼30 s for the ceramic phase formation. A high-level compaction due to centrifugal forces and a liquid phase sintering approach provided a dense gradient ceramic structure formed by oxide grains cemented by a glassy phase and bonded with a steel substrate through a thin iron layer. The coatings were successfully produced onto the inner surface of carbon and stainless steels' tubes of up to 12 ft-lengths and standard dimensions from 2 to 3/8″ to 7.5" OD. The coatings were tested, for the first time, in wear and high-temperature corrosive environments, e.g., in steam–H 2 S–CO 2 gases and molten salts, with encouraging results due to high contents of Al 2 O 3 and some other oxides and consolidated ceramic structure. They can be recommended for applications in high-temperature (900 °C and greater) corrosive environments and erosive flows. [ABSTRACT FROM AUTHOR]

The destruction of various structural materials and products in aggressive atmospheric conditions demands for the development of more resistant and improved oligomers and polymers for adhesive coatings with barrier properties, which could prevent corrosion and rapid aging of metals and polymers. In this article, we demonstrate the synthesis of novel polysilsesquioxane containing a covalently bonded eugenol, being a corrosion inhibitor of natural origin. The research demonstrates the synthesis of a monomer from eugenol and MPTMS by the UV‐initiated thiol‐ene reaction. Polysilsesquioxanes were synthesized by hydrolytic and acidohydrolytic polycondensation methods. The 29Si NMR spectroscopy shows the difference in the chemical structures of the obtained products. The synthesized polysilsesquioxanes have a glass transition temperature of −6.5 °C and −7.2 °C for hydrolytic and acidohydrolytic polycondensation, respectively. At the same time, rheokinetics shows a significant difference in the curing of polysilsesquioxanes obtained by two different methods in the temperature range of 150–190 °C. So, it was shown that the product obtained by acidohydrolytic polycondensation exhibited much lower ability for the formation of cross‐linked networks. The product, obtained by hydrolytic polycondensation, exhibited good coating performance, and the obtained coatings showed high anticorrosive efficiency. [ABSTRACT FROM AUTHOR]

Fouling in continuous reactors presents a significant challenge in the process intensification of specialty polymers. While in continuous stirred tank reactors (CSTRs) fouling is minimal, tubular reactors experience severe fouling, sometimes leading to complete blockage. Therefore, it is crucial to understand process and design conditions contributing to deposit formation. In this work, the impact of geometry, mixing elements, novel coatings, and ultrasonic waves are tested on tubular reactors for the polymerization of polyvinylpyrrolidone. [ABSTRACT FROM AUTHOR]

Purpose: High-nitrogen steel is a common material for the manufacture of drilling equipment such as drill collars. However, its poor surface properties often limit its applications. The purpose of this paper is to find a way to enhance the surface performance of high-nitrogen steel, which is expected to improve the wear resistance of high-nitrogen steel. Design/methodology/approach: The CoCrNi and CoCrFeNi medium-entropy alloy (MEA) coatings were prepared on high-nitrogen steel substrate by laser cladding technology. The microstructure, phase composition and element distribution of the fabricated coatings were investigated using scanning electronic microscopy, electron backscatter diffraction and X-ray diffraction. The phase structure, phase stability and structural stability of the CoCrNi and CoCrFeNi MEAs were investigated in combination with phase diagram calculation and molecular dynamics. Then the wear tests were carried out for coatings. Findings: The results show that both prepared MEA coatings have good quality and contain a single face-centered cubic phase. The wear performance of MEA coatings is improved by the refinement of grain size and the increase of dislocation density. Due to the addition of Fe atoms, the lattice distortion of the CoCrFeNi system increased, resulting in a higher dislocation density of the coating. Cr atoms in the CoCrFeNi system are the largest, and the local lattice distortions induced by them are greater. Through this study, MEA coatings with high hardness can be expanded to drilling field applications. Originality/value: CoCrFeNi and CoCrNi MEA coatings were successfully prepared on the surface of high-nitrogen steel for the first time without obvious defects. The micromorphology and grain orientation of the different kinds of coatings were discussed in detail. The hardness-strengthening mechanism and structure stability of the coatings were illustrated by experiments and molecular dynamics simulations. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0116/ [ABSTRACT FROM AUTHOR]

Multi-principal-element alloys (MPEAs) exhibit superior strength and good ductility. However, tribological properties of FeCrNi MPEAs remain unknown at nanoscale and complex environments. Here, we investigate the effects of scratching speed, depth, and temperature on microstructural and tribological characteristics of FeCrNi using molecular dynamics simulations combined with an elevated temperature tribological experiment. The scratching force experiences the increase stage, the undulated stage, and the stable stage due to chip formation. Compared to traditional alloy coatings, low force enhances the useful life. With increased speed, the friction coefficient decreases, agreeing with previous work. High speed impacting includes severe local plastic deformation, from dislocation to amorphization. As the scratching depth increases, the average scratch force and friction coefficient increases owing to material accumulation in front of the abrasive particles. The surface morphology and dislocation behavior are significantly different during the scratching process. In addition, we revealed a temperature-dependent friction mechanism. FeCrNi MPEAs have excellent wear resistance at an intermediate temperature, which is attributed to the high Cr content promoting the formation of the compact oxide layer. This work provides atomic-scale mechanistic insights into the tribological behavior of FeCrNi, and would be applied to the design of MPEAs with high performance. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) and its alloys have received much attention in the aerospace, transportation, automotive industry, and military equipment fields due to their unique chemical and physical properties, such as their low density and high specific strength, particularly as the lightest structural metal materials, with the opportunity to achieve the design of lighter engineering systems. With the continuous improvement of processing technology, the application scope of magnesium alloy is rapidly expanding, and market demand is increasing. However, because of its significant electronegativity (2.37 V) and loose naturally formed oxide coating, magnesium has low corrosion resistance in comparison to other structural metal elements, severely limiting its large‐scale use. This review summarizes several typical anticorrosion methods for magnesium alloys, including chemical conversion coating treatment, anodic oxide film treatment, micro‐arc oxidation treatment, laser surface treatment, ion implantation, physical vapor deposition, and superhydrophobic coating. In most cases, the corrosion resistance of magnesium and its alloys has improved, but it has a certain degree of environmental damage. It is hoped that this review will contribute to further developing magnesium alloy materials in the field of preservative coating. [ABSTRACT FROM AUTHOR]

AbstractNanodiamonds are unique spherical carbon nano-entities having the advantages of very high surface area and high optical, thermal, wear and strength characteristics. Like other carbonaceous nanoparticles (like fullerene, graphene or carbon nanotube), nanodiamond nano-reinforcements have been investigated for the significant types of polymeric matrices (such as thermosets, thermoplastics, rubbers) nanocomposites. Consequently, this overview was planned to systematically describe the current scientific status of the nanodiamonds reinforced thermoplastic nanomaterials. In this regard, polyamide/nanodiamonds, polyimide/nanodiamonds and polystyrene/nanodiamonds nanocomposites have been fabricated using the facile solution, in-situ and melt mixing techniques. We suggest that including nanodiamonds in polyamides and polyimides increased their engineering characteristics, like mechanical properties and thermal stability, of the resulting nanocomposites due to a distinct interface formation and their compatibilization effects toward these matrices. Correspondingly, including nanodiamonds in polystyrene has been observed to increase the intrinsically low strength/toughness features of this polymer. Predominantly, nano-reinforcement and miscibility effects of the nanodiamonds with the polystyrene and their mutual matrix-nanofiller synergies were responsible to improve the overall microstructural and physical properties of the resulting nanocomposites. As per our analysis, the research reports so far on the important categories of the nanodiamonds reinforced thermoplastic matrix nanocomposites have shown important technical applications in the fields of high-tech coatings, membranes and energy devices. [ABSTRACT FROM AUTHOR]

In this study, inorganic-organic coatings composed of titanium dioxide (TiO 2) as the ceramic component and poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP) as the polymer matrix, hybridized with nano-TiO 2 particles, were developed for protecting mild steel (MS) from corrosion. Prior to TiO 2 coating deposition, the MS substrates were pretreated with a bioinspired sub-layer of polydopamine to improve the surface coating adhesion, followed by uniform co-deposition of PVDF-HFP with varying concentrations of embedded nano-TiO 2. The inclusion of nano-TiO 2 further reinforces and densifies PVDF-HFP, providing added corrosion protection. The fabricated coatings were characterized by microscopy, spectroscopy, and diffraction technique, while the corrosion protection properties were evaluated by impedance, potentiodynamic polarization, salt spray, and cyclic corrosion tests. Results showed that both the PVDF-HFP matrix and TiO 2 contents had substantial effects on the coatings' thermal stability, hydrophobicity, and surface mechanical properties. The coatings also exhibited satisfactory corrosion resistance, with increased impedance modulus to roughly sixteen orders of magnitude for the TiO 2 -PVDF-HFP coating containing 0.5 g/L TiO 2 , relative to the untreated MS substrate. This result can be attributed to the low surface energy of PVDF-HFP, coupled with the dense structure and added physical barrier of nano-TiO 2. Overall, these hybrid polymer/ceramic coatings are poised to help design other highly resilient and hydrophobic surface coatings with durable protection against corrosion. [ABSTRACT FROM AUTHOR]

In recent years, biopolymer coatings have emerged as an effective approach for extending the shelf life of edible fruits. The invention of biopolymer coverings has emerged as an innovation for extending fruit shelf life. Natural polymers, like chitosan, alginate, and pectin, are used to create these surfaces, which have several uses, including creating a barrier that prevents water evaporation, the spread of living microbes, and respiratory movement. These biopolymer coatings' primary benefits are their environmental friendliness and lack of damage. This study highlights the advancements made in the creation and usage of biopolymer coatings, highlighting how well they preserve fruit quality, reduce post-harvest losses, and satisfy consumer demand for natural preservation methods. This study discusses the usefulness of the biopolymer coating in terms of preserving fruit quality, reducing waste, and extending the product's shelf life. Biopolymer coatings' potential as a sustainable solution for synthetic preservatives in the fruit sector is highlighted as are formulation process advances that combine natural ingredients and environmental implications. This essay focuses on the essential methods, such as new natural additives, as well as the environmental effect of biopolymer coatings, which are safe and healthy commercial alternatives. [ABSTRACT FROM AUTHOR]

The AZ91 magnesium alloy was subjected to a complex treatment involving age hardening (supersaturation and artificial aging) and simultaneous surface layer modification. The specimens were supersaturated in contact with a mixture containing varying concentrations of zinc chloride, followed by cooling either in air or water. After supersaturation, the specimens were subjected to artificial aging and then air-cooled. This process resulted in the formation of a surface layer made of zinc-rich phases. The thickness and microstructure of the surface layer were influenced by the process parameters, namely, the zinc chloride content in the mixture and the cooling rate during supersaturation. The treated specimens exhibited favorable tensile strength and greater elongation compared to the as-cast AZ91 alloy, with values comparable to those of the alloy subjected to standard T6 tempering. No cracking of the layer was observed under moderate deformation, though greater deformation resulted in the formation of cracks, primarily in the areas containing the Mg5Al2Zn2 intermetallic phase. The produced layer demonstrated strong metallurgical bonding to the AZ91 substrate. [ABSTRACT FROM AUTHOR]

The oxidation resistance of Hf0.28B0.72 and Hf0.11Al0.20B0.69 thin films was investigated comparatively at 700 °C for up to 8 h. Single-phase solid solution thin films were co-sputtered from HfB2 and AlB2 compound targets. After oxidation at 700 °C for 8 h an oxide scale thickness of 31 ± 2 nm was formed on Hf0.11Al0.20B0.69 which corresponds to 14% of the scale thickness measured on Hf0.28B0.72. The improved oxidation resistance can be rationalized based on the chemical composition and the morphology of the formed oxide scales. On Hf0.28B0.72 the formation of a porous, O, Hf, and B-containing scale and the formation of crystalline HfO2 is observed. Whereas on Hf0.11Al0.20B0.69 a dense, primarily amorphous scale containing O, Al, B as well as approximately 3 at% of Hf forms, which reduces the oxidation kinetics significantly by passivation. Benchmarking Hf0.11Al0.20B0.69 with Ti–Al-based boride and nitride thin films with similar Al concentrations reveals superior oxidation behavior of the Hf-Al-based thin film. The incorporation of few at% of Hf in the oxide scale decelerates oxidation kinetics at 700 °C and leads to a reduction in oxide scale thickness of 21% and 47% compared to Ti0.12Al0.21B0.67 and Ti0.27Al0.21N0.52, respectively. Contrary to Ti–Al-based diborides, Hf0.11Al0.20B0.69 shows excellent oxidation behavior despite B-richness. [ABSTRACT FROM AUTHOR]

A robust microextraction device in the form of a glass vial internally coated with metal–organic frameworks (MOFs) is designed, fabricated by in situ growth of different Zr‐based MOFs, and fully characterized for its novel use as an analytical platform. This device, uniformly coated by the MOF, ensures high simplicity and short times when used as an analytical microextraction tool, as the device acts as both the sample container and the extraction device, being tested for monitoring the presence of a group of endocrine‐disrupting chemicals in pool waters. The thin film format and MOF nature allow for high extraction efficiency and preconcentration of these target contaminants. Adsorption and desorption of the analytes are studied through kinetic experiments, with uptakes up to 90% for propylparaben in the UiO‐66‐abdc vial, and an extremely fast desorption in just seconds. The UiO‐66‐abdc vial does not require more than 15 min to perform a complete extraction‐desorption cycle, with limits of detection down to 0.10 µg L−1 in pool waters. The MOF‐coated vials are demonstrated to be easily (and highly) reusable by simple washing for a few min followed by drying. The simplicity of the method can be pushed further working in static mode or by a simple manual shaking. [ABSTRACT FROM AUTHOR]

This study investigates the sustainability and efficacy of coatings for archaeological silver. Building on a survey of current practices in silver conservation and a literature review, a group of Chimú (Peruvian north coast, 1100–1400 CE) silver alloy items in the National Museum of the American Indian collection serves as a case study. Assessing treatment options for 80 Chimú items led to the investigation into the implications of introducing a new coating campaign. Experimentation was carried out with coupons approximating the composition and manufacture of Chimú silver. Four conservation grade materials, Agateen® 27, Acrysol® WS24, Paraloid® B-72, and Regalrez® 1126, were tested for protection efficacy in a humid, sulfur-containing environment. Analysis with X-ray fluorescence spectroscopy (XRF), scanning electron microscopy energy-dispersive X-ray spectroscopy (SEM-EDX), and imaging at several phases throughout the experiment provided data on the interaction of the metal and the coating and the effects of coating and re-coating. Oddy testing and Fourier transform infrared spectroscopy (FTIR) conducted on these prepared coatings helped determine their suitability for long-term use. Results indicate that not coating is more appropriate for preservation than coating with any of the four materials tested. [ABSTRACT FROM AUTHOR]

Sapodilla (Manilkara zapota) is a climacteric fruit that ripens quickly and is highly perishable, making it difficult to commercialize. This study examined the effect of xanthan gum (Xan) enriched with oleic acid (ol) on chilling injury and postharvest quality of sapodilla fruit during 40 days of storage at 8 ± 1°C and 85%–90% relative humidity. The results showed that the treatments effectively controlled fruit browning, with the least browning observed in the Xan 0.1 and Xan 0.1 + Ol coatings. At the end of storage, all treatments except Xan 0.1 reduced lipid peroxidation and electrolyte leakage. Moreover, the fruit treated with Xan 0.1 + Ol also displayed the highest levels of phenolic compounds, flavonoids, and antioxidant activity. Additionally, the Xan 0.1 + Ol and Xan 0.1 treatments had the greatest activity of peroxidase (POD) and phenylalanine ammonia-lyase (PAL) enzymes. Xan 0.1 + Ol had the lowest activity of the polyphenol oxidase (PPO) enzyme. Overall, the application of the Xan 0.1 + Ol coating proved to be a beneficial edible treatment for minimizing cold-induced damage and improving the quality of stored sapodilla fruit. Generally, the use of oleic acid-enriched xanthan gum in sapodilla fruit has significantly improved preservation and quality. [ABSTRACT FROM AUTHOR]

The interrelation of the structure and tribomechanical characteristics of the metal materials that comprise the friction members is considered, specifically the interactions between copper alloy – steel and steel with Cu – Zn coatings – steel. The formation of a wear-resistant structural state in the operational layer of Cu – Zn alloys with concentrations of up to 93% of Zn is described. The tribomechanical efficiency of Cu – Zn coatings obtained by two methods is considered from the standpoint of the regularities of the formation of a wear-resistant structure, namely friction-mechanical treatment and cold gas-dynamic spraying. It is demonstrated that regardless of the technology used for the surface modification of a steel product with a copper-based alloy, a secondary self-organizing structure with parameters characteristic of the wear-resistant state is formed in the operational layer as a result of contact deformation, which ensures an increase in the durability of tribological contacts. [ABSTRACT FROM AUTHOR]

The use of polymer latexes for high‐performance coatings is challenging as the properties required to allow for film formation at reasonable temperatures tend to result in films with relatively poor mechanical properties. In this review, routes to overcome this so‐called film‐formation dilemma are discussed. First, the use of coalescing agents, focusing in particular on more recent approaches to minimize the use of volatile organic compounds (VOCs), is reviewed. Subsequently, approaches that utilize hybrid latexes are considered. This includes the use of high/low Tg latex blends, nanocomposites that include a second, non‐polymeric phase, and multiphase latexes. Finally, the use of crosslinking technologies is considered, with a focus on necessary developments to reduce environmental impact. The review concludes with a summary and a discussion of possible future directions for research. [ABSTRACT FROM AUTHOR]

In this article, the surface modification methods of hollow glass microspheres and their applications in coatings were briefly introduced. The latest research progress in thermal insulation coatings, fireproof coatings, wave-absorbing coatings and anticorrosive coatings was summarized, and the future direction of the application of hollow glass microspheres in coatings was prospected. [ABSTRACT FROM AUTHOR]

Corrosion is a spontaneous process that can be slowed down, though not entirely prevented, through various methods. The most common method for protecting metals against corrosion involves the application of coatings, with nearly three-quarters of metal structures currently benefiting from organic coatings. In addition to providing effective corrosion protection, modern coatings are expected to be environmentally friendly. Presently, there is growing interest in researching coatings based on water-soluble natural polymers containing active chemical compounds, such as corrosion inhibitors. One such polymer is chitosan, which exhibits excellent film-forming ability in acidic aqueous solutions, making it well suited for diverse protective coating applications. This study explores the possibility of applying a chitosan-based coating with the addition of TiO2 and eucalyptol for the protection of steel against acid corrosion. The results confirmed that the tested chitosan-based coatings must incorporate an inhibitor to have a protective effect on the steel surface, since these coatings show a corrosive effect without an inhibitor. Although coatings based on chitosan and titanium dioxide with the addition of eucalyptol demonstrate protective effects, the duration of these effects is limited. Consequently, this method of protection could be suitable only for temporary protection of steel against acid corrosion. [ABSTRACT FROM AUTHOR]

A novel approach to the fabrication of thin-film supported metal oxide membranes was investigated. Nanocoatings were obtained by the condensed layer deposition of TiO2 on tubular microporous supports, applying multiple consecutive layers of TiO2/polyaniline. The surface, cross-sectional structure, and morphology of the materials were investigated by electron microscopy. Their membrane-related properties were explored by permeability measurements, rejection, and fouling analysis, using polyethylene glycol (PEG) as test molecules. The SEM images showed that TiO2 was successfully deposited on the surface, creating a layer with partial coverage of the support after each layer was deposited; consequently, the permeability of the membranes decreased gradually. Overall, the results of the flux and permeability of the membranes confirmed the coating. The transmembrane pressure (TMP) increased with each coating layer, while the rejection of the membrane showed gradual improvement. [ABSTRACT FROM AUTHOR]

Polymer coatings are widely used in industries for protection, decoration, and specific applications, typically including volatile organic compounds (VOCs) to achieve low viscosity. The growing environmental concerns and the anticipated limits on fossil feedstock have driven the coating industry towards eco-friendly alternatives, with UV-curing technology emerging as a promising solution due to its energy efficiency, low-temperature operation, reduced VOC emissions, and high curing speed. Polyurethane acrylates (PUAs) are critical in UV-curable formulations, offering excellent flexibility, impact strength, optical, and adhesion properties. However, UV-cured PUA coatings face limitations in thermal stability and tensile strength, which can be addressed by incorporating fillers. This study investigates the effects of multi-functionalized hexagonal boron nitride (hBN) nanoparticles on the mechanical, thermal, optical, and adhesion properties of UV-cured PUA films and coatings for pre-coated metals. The results demonstrated that incorporating hBN nanoparticles enhanced the mechanical and thermal properties of the nanocomposite films, with optimal performance observed at 0.5% hBN loading. Despite the improved properties, the FTIR spectra indicated that the low concentration of hBN did not produce significant changes, potentially due to the overshadowing signals from the difunctional polyurethane acrylate. [ABSTRACT FROM AUTHOR]

Molecular dynamic simulation along with experiments was used to study polycarbonate (PC) molecular conformation on composite interfacial properties. The interlaminar shear strength (ILSS) variations of composites with carbon fiber roughness were quite different between sized and unsized carbon fibers, which seem to conflict with the theory that rougher surface is harder to wet. By the results of molecular dynamic simulation, it was found that the conformation of PC molecules through solvent intervention could be higher, which is conducive to the formation of π–π stacking conformation between PC and carbon fibers and benefits the interface interaction, resultantly affecting the ILSS more when the carbon fiber surface area was low. When the specific surface area was high enough, the ILSS gets to a saturation value, because the fracture area changes from the interface to the matrix. It is concluded that the effects of sizing on ILSS varied with carbon fiber surface roughness, and the molecular conformation of the matrix affected by sizing or processing must be considered. Therefore, it is important to enhance the physical interactions with carbon fiber for thermoplastic resin matrixes. [ABSTRACT FROM AUTHOR]

Within this study, the alloy NiAl–2.5Ta–7.5Cr is investigated as a new matrix material for cBN-reinforced abrasive turbine blade tip coatings as currently used NiCoCrAlY matrix alloys suffer from insufficient strength at the high operating temperatures. Laser-based directed energy deposition with blown powder was applied to produce cBN reinforced NiAl-based coatings on monocrystalline CMSX-4 substrates. For this, powdery titanium-coated cBN and NiAl–2.5Ta–7.5Cr material were co-injected into the process zone to achieve an in situ formation of a NiAl–2.5Ta–7.5Cr/cBN composite. In order to overcome challenges such as cracking susceptibility, inductive preheating of the substrate up to 800 °C was used. Optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, as well as electron backscatter diffraction were applied to analyse the fabricated samples' microstructure. Additionally, the mechanical properties were evaluated by means of microhardness mappings. This work demonstrates the feasibility of in situ forming a metal matrix composite with a homogeneous distribution of cBN particles. The results show the beneficial effect of high-temperature preheating on the crack formation. However, the study also reveals challenges such as cracking induced by the injected cBN particles as well as severe intermixing of substrate and coating, which yields spatially resolved deviations in the chemical composition and resulting variations in microstructure and hardness. [ABSTRACT FROM AUTHOR]

Uniformly coating micronic particles with metals is of main interest for a broad range of applications. This study demonstrates the feasibility of depositing pure copper on the surface of micronic alumina particles by the fluidized bed chemical vapor deposition process from the cheap and nontoxic copper acetylacetonate precursor. Thanks to the development of a preconditioning protocol, a complete fluidization of the particles organized as porous agglomerates was reached. The coating of the individual particles was favored by using conditions involving low deposition rates. The influence of key operating parameters on the process behavior and on the characteristics of the deposit was studied. The deposited copper was of cubic crystal structure without carbon nor oxide contamination. [ABSTRACT FROM AUTHOR]

Degradation of coatings and structural materials due to high temperature corrosion in the presence of molten salt environment is a major concern for critical infrastructure applications to meet its commercial viability. The choice of high value coatings and structural (construction parts) materials comes with challenges, and therefore data centric approach may accelerate change in discovery and data practices. This research aims to use machine learning (ML) approach to estimate corrosion rates of materials when operated at high temperatures conditions (e.g., nuclear, geothermal, oxidation (dry/wet), solar applications) but geared towards nuclear thermochemical cycles. Published data related to materials (structural and coatings materials), their composition and manufacturing, including corrosion environment were gathered and analysed. Analysis demonstrated that random forest regression model is highly precise compared to other models. Assessment indicates that very limited sets of materials are likely to survive high temperature corrosive environment for extended period of exposure. While a higher quality and larger dataset are required to accurately predict the corrosion rate, the findings demonstrated the value of ML's regression and data mining capabilities for corrosion data analysis. With the research gap in material selection strategies, proposed research will be critical to advancing data analytics approach exploiting their properties for high temperature corrosion applications. [ABSTRACT FROM AUTHOR]

This study focuses on the development and characterization of polyurethane coatings using castor oil as a renewable source. Most castor oil-based polyurethane paints have a rather long curing process. Therefore, this study focused on the preparation of a polyurethane paint based on raw castor oil without the need for chemical modifications, in a quick and cost-effective manner. The methodology involved the preparation of the paint using castor oil, isocyanate, calcium carbonate, titanium dioxide, additives and solvents. The coatings were then characterized and compared with industrial polyurethane paint in terms of thermal properties, rheology, UV degradation, adhesion, water resistance, and resistance to salt spray corrosion. Results showed that the castor oil-based paint exhibited comparable rheological behavior to the commercial paint, with superior thermal stability. However, the industrial paint showed better performance in UV degradation and similar behavior in the adhesion tests. In the water resistance test, the castor oil-based paint proved to be superior to the commercial paint. The salt spray corrosion test revealed that the castor oil-based paint had superior corrosion resistance due to the higher proportion of castor oil in the formulation, which increases the crosslinking of the chains. This work offers a simple and fast method to prepare and substitute petrochemical polyols with castor oil in order to use renewable sources with promising properties. [ABSTRACT FROM AUTHOR]

This paper presents a study on thermally sprayed coatings. Coatings produced by high-velocity oxygen–fuel spraying HVOF and plasma spraying deposited on the A03590 aluminum casting alloy are tested. The subject of this research concerns coatings based on tungsten carbide WC, chromium carbide Cr3C2, composite coatings NiCrSiB + 2.5%Fe + 2.5%Cr, mixtures of tungsten and chromium powders WC-CrC-Ni, mixtures of carbide powders with the Cr3C2-NiCr + the composite 5% NiCrBSi and WC-Co + 5% NiCrBSi. The aim of this research is to find a coating most resistant to the erosive impact of particles contained in the medium centrifuged by industrial rotors. The suitability of the coating is determined by its high level of microhardness. The hardest coatings are selected from the coatings tested and subjected to abrasion tests against a sand particle impact jet and the centrifugation of a medium with corundum particles. It is found that the most favorable anti-erosion properties are demonstrated by a coating composed of a mixture of tungsten carbide and chromium carbide WC-CrC-Ni powders. It is concluded that the greatest resistance of this coating to the erosive impact of the particle jet results from the synergistic enhancement of the most favorable features of both cermets. [ABSTRACT FROM AUTHOR]

SiBCN films are synthesized by plasma-enhanced chemical vapor deposition at a reduced pressure and 500-600 °C. Organoelement silicon and boron compounds are selected as precursors, namely, hexamethyldisilazane HN(SiMe3)2 and triethylaminoborane Et3N·BH3 that were not used previously in the synthesis of SiBCN films. Vapor flows of initial compounds and additional gas (ammonia) were separately supplied to the reactor without premixing. The chemical bonding structure, elemental composition, surface morphology, and film deposition rate are studied by FTIR, XPS, wave dispersive X-ray spectroscopy, SEM, and Raman spectroscopy techniques. The surface morphology analysis of the samples shows that the films are smooth, homogeneous, and uniform without features. Variation of precursor concentrations in the initial mixture allows changes in the film composition in a wide range. The boron concentration in four-component coatings reaches 45 at.%. The study of chemical bonding structures of the films reveals the occurrence of Si–C, Si–N, B–N, C–H bonds along with the hybrid BCnN3–n bond. [ABSTRACT FROM AUTHOR]

Nanoparticle formation by Spark Discharge Aerosol Generation offers low‐cost fabrication of nanoparticles, without the use of chemicals or vacuum. It produces aerosol particles of a few nanometers in size with high purity. In this work, copper‐based ‐CuO (tenorite) and Cu‐ nanoparticles are produced, characterized and used to modify face mask air filters, achieving the introduction of antibacterial and antiviral properties. A range of characterization techniques have been employed, down to the atomic level. The majority of the particles are CuO (of a few nanometers in size that agglomerate to form aggregates), the remainder being a small number of larger Cu particles. The particles were deposited on various substrates, mainly fiber filters in order to study them and use them as biocidal agents. On face masks, their antibacterial activity against Escherichia coli (E.coli) results in a 100 % decrease in bacteria cell viability. Their antiviral activity on face masks results in a 90 % reduction of the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS‐CoV‐2) viability, 15 minutes post the application of the virus stock solution. This highlights the effectiveness of this approach, its simplicity, its low cost and its excellent environmental credentials. [ABSTRACT FROM AUTHOR]

The hydroxyapatite and copper-doped hydroxyapatite coatings (Ca10−xCux(PO4)6(OH)2; xCu = 0, 0.03; HAp and 3CuHAp) were obtained by the vacuum deposition technique. Then, both coatings were analyzed by the X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and water contact angle techniques. Information regarding the in vitro antibacterial activity and biological evaluation were obtained. The XRD studies confirmed that the obtained thin films consist of a single phase associated with hydroxyapatite (HAp). The obtained 2D and 3D SEM images did not show cracks or other types of surface defects. The FTIR studies' results proved the presence of vibrational bands characteristic of the hydroxyapatite structure in the studied coating. Moreover, information regarding the HAp and 3CuHAp surface wettability was obtained by water contact angle measurements. The biocompatibility of the HAp and 3CuHAp coatings was evaluated using the HeLa and MG63 cell lines. The cytotoxicity evaluation of the coatings was performed by assessing the cell viability through the MTT assay after incubation with the HAp and 3CuHAp coatings for 24, 48, and 72 h. The results proved that the 3CuHAp coatings exhibited good biocompatible activity for all the tested intervals. The ability of Pseudomonas aeruginosa 27853 ATCC (P. aeruginosa) cells to adhere to and develop on the surface of the HAp and 3CuHAp coatings was investigated using AFM studies. The AFM studies revealed that the 3CuHAp coatings inhibited the formation of P. aeruginosa biofilms. The AFM data indicated that P. aeruginosa's attachment and development on the 3CuHAp coatings were significantly inhibited within the first 24 h. Both the 2D and 3D topographies showed a rapid decrease in attached bacterial cells over time, with a significant reduction observed after 72 h of exposure. Our studies suggest that 3CuHAp coatings could be suitable candidates for biomedical uses such as the development of new antimicrobial agents. [ABSTRACT FROM AUTHOR]

Due to the intricate and volatile nature of the service environment surrounding prestressing anchoring materials, stress corrosion poses a significant challenge to the sustained stability of underground reinforcement systems. Consequently, it is imperative to identify effective countermeasures against stress corrosion failure in cable bolts within deep underground environments, thereby ensuring the safety of deep resource extraction processes. In this study, the influence of various coatings on the stress corrosion resistance of cable bolts was meticulously examined and evaluated using specifically designed stress-corrosion-testing systems. The specimens were subjected to loading using four-point bending frames and exposed to simulated underground corrosive environments. A detailed analysis and comparison of the failure patterns and mechanisms of specimens coated with different materials were conducted through the meticulous observation of fractographic features. The results revealed stark differences in the stress corrosion behavior of coated and uncoated bolts. Notably, epoxy coatings and chlorinated rubber coatings exhibited superior anti-corrosion capabilities. Conversely, galvanized layers demonstrated the weakest effect due to their sacrificial anti-corrosion mechanism. Furthermore, the effectiveness of the coatings was found to be closely linked to the curing agent and additives used. The findings provide valuable insights for the design and selection of coatings that can enhance the durability and reliability of cable bolts in deep underground environments. [ABSTRACT FROM AUTHOR]

GaN is more stable than most metal oxide semiconductors for the photocatalytic degradation of organic pollutants in harsh conditions, while its catalytic efficiency has been difficult to be substantially improved. In this study, the tribocatalytic degradation of organic dyes by GaN nanoparticles has been investigated. Stimulated through magnetic stirring using homemade Teflon magnetic rotary disks in glass beakers, the GaN nanoparticles were found to induce negligible degradation in rhodamine B (RhB) and methyl orange (MO) solutions. Surprisingly, the degradation was greatly enhanced in beakers with Ti and Al2O3 coatings on their bottoms: 99.2% and 99.8% of the 20 mg/L RhB solutions were degraded in 3 h for the Ti and Al2O3 coatings, respectively, and 56% and 60.2% of the 20 mg/L MO solutions were degraded in 24 h for the Ti and Al2O3 coatings, respectively. Moreover, the MO molecules were only broken into smaller organic molecules for the Ti coating, while they were completely degraded for the Al2O3 coating. These findings are important for the catalytic degradation of organic pollutants by GaN in harsh environments and for achieving a better understanding of tribocatalysis as well. [ABSTRACT FROM AUTHOR]

Integration of bioelectronic devices in clinical practice is expanding rapidly, focusing on conditions ranging from sensory to neurological and mental health disorders. While platinum (Pt) electrodes in neuromodulation devices such as cochlear implants and deep brain stimulators have shown promising results, challenges still affect their long‐term performance. Key among these are electrode and device longevity in vivo, and formation of encapsulating fibrous tissue. To overcome these challenges, organic conductors with unique chemical and physical properties are being explored. They hold great promise as coatings for neural interfaces, offering more rapid regulatory pathways and clinical implementation than standalone bioelectronics. This study provides a comprehensive review of the potential benefits of organic coatings in neuromodulation electrodes and the challenges that limit their effective integration into existing devices. It discusses issues related to metallic electrode use and introduces physical, electrical, and biological properties of organic coatings applied in neuromodulation. Furthermore, previously reported challenges related to organic coating stability, durability, manufacturing, and biocompatibility are thoroughly reviewed and proposed coating adhesion mechanisms are summarized. Understanding organic coating properties, modifications, and current challenges of organic coatings in clinical and industrial settings is expected to provide valuable insights for their future development and integration into organic bioelectronics. [ABSTRACT FROM AUTHOR]

This paper reports the fabrication, characterization, and environmental impact analysis of a super-oleophobic (under water) and super-hydrophilic mesh membrane for oily water treatment. In order to prepare mesh membrane, Titania nanoparticles (NPs) were spray coated on mesh stainless steel followed by calcination at 500 °C. After that, the Titania-coated mesh membrane was characterized using contact angle goniometry (CA), XRD, FE-SEM, EDX and elemental mapping. The FE-SEM, EDX, elemental mapping and XRD results confirmed that the Titania NPs were successfully coated on the surface of mesh membrane. CA results demonstrated that the prepared mesh membrane is super-hydrophilic and super-oleo phobic under water conditions, making it suitable for oil/water separation. Subsequently, life cycle assessment (LCA) was performed to determine the environmental impacts of Titania NPs-coated mesh membrane fabrication process. LCA results indicate that electricity and nitrogen contributed the most toward the eighteen environmental impact categories considered for this study. [ABSTRACT FROM AUTHOR]

To assess the strength of coatings under multi‐axial stress conditions, a method was developed to evaluate the biaxial strength of thin silicon carbide (SiC) coatings using a ring‐on‐ring test. A graphite substrate was used as an intermediary to transmit stress from the load ring to the coated specimen, and the thin coating was subjected to a uniform equi‐biaxial stress. The strain in the thin film was continuously monitored using digital image correlation, allowing the identification of the time at which and when the initial crack occurred; the stress applied to the loading area at time was determined to be the fracture strength of the thin SiC films. The obtained fracture strength ranged from 209 to 1014 MPa and was dependent on specimen volume. Notably, the thinnest specimen exhibited the highest strength, whereas the strengths of thicker specimens approached previously reported bulk strengths. [ABSTRACT FROM AUTHOR]

• For the first time, fire occurrence in heritage facilities and the use of fire-retardant and fire-resistant coatings are discussed in a comprehensive approach. • Studies on the development and application of fire-retardant and fire-resistant coatings, addressing the different mechanisms of action and the main formulations, are reviewed. • The leading causes of fires, the factors contributing to their spread, and the fire protection measures applied to heritage facilities are described. • Based on published research, the use of fire-retardant and fire-resistant coatings in museum and storage environments is addressed, and an overview of the limited research on the application of these coatings in heritage environments is provided. • The value of fire-protective coatings is recognised as an additional measure to collections in fire-prone locations or for facilities more susceptible to fire-related events. Fire is one of the most damaging deterioration agents in a short time of action. It can cause considerable damage, leading to the loss of lives and possessions. Concerning fire safety recommendations, buildings must be protected by an integrated system of passive and active measures. Two passive measures widely used in many industries are fire-retardant and fire-resistant coatings. These systems provide a fire-protective layer to the surfaces of flammable and non-flammable materials, delaying or preventing their ignition, reducing the heat transfer from the source to the substrate and decreasing the flame spread and the release of smoke and toxic gases. When exposed to fire, according to the different mechanisms of action, fire-protective coatings (FPC) can be classified as non-intumescent and intumescent. Despite being widely mentioned in heritage fire safety guidelines, studies on their application in the field are still scarce. Namely, research on the safety and efficacy of their application near collections (in support materials) and systematic studies comparing different formulations. Therefore, this research assembles interdisciplinary studies on the use of FPC to deepen knowledge and theoretically identify the feasibility of their application in collection support/storage materials or exhibition furniture (bookshelves, cabinets, plinths) in heritage environments. [ABSTRACT FROM AUTHOR]

This work aims at studying the interfacial behavior of functionally graded coatings (FGCs) on different substrates, here modeled as asymmetric double cantilever beams, in line with the experimental tests. An enhanced beam theory (EBT) is proposed to treat the mixed-mode phenomena in such specimens, whose interface is considered as an assembly of two components of the coating/substrate system bonded together partially by an elastic interface. This last one is modeled as a continuous distribution of elastic–brittle springs acting along the tangential and/or normal direction depending on the interfacial mixed-mode condition. Starting with the Timoshenko beam theory, we determine the differential equations of the problem directly expressed in terms of the unknown interfacial stresses, both in the normal and tangential directions. Different distribution laws are implemented to define the functional graduation of the material in the thickness direction of the specimens, whose variation is demonstrated numerically to affect both the local and global response in terms of interfacial stresses, internal actions, energy quantities and load–displacement curves. The good accuracy of the proposed method is verified against predictions by a classical single beam theory (SBT), with interesting results that could serve as reference solutions for more expensive experimental investigations on the topic. [ABSTRACT FROM AUTHOR]

This study investigates the impact of combined texturing by micromachining and chemical functionalization on the wetting behavior and water condensation on stainless steel 304. The transition from Wenzel to Cassie-Baxter or impregnated Cassie-Baxter regimes is investigated. Understanding this transition is critical for advancing surface engineering, as it enables precise control over wetting behavior for various applications. Herein, we report on the wire EDM (wEDM) machining on stainless steel 304 to produce two distinct microstructure patterns with directional canals or pyramidal structure, and their performance in water condensation. These patterns significantly impact water condensation performance. wEDM is employed to create surface roughness, followed by phosphoric acid treatment and chemical functionalization with trichloro-1H,1H,2H,2H-perfluorooctyl silane. Contact angle measurements reveal a synergistic effect between groove direction and silane coating, leading to hydrophobic surfaces and dropwise water condensation. Specimens with directional canals exhibit a contact angle of 150°, while specimens with pyramidal structures exhibit 151o. Roll-off angle experiments showcased distinct behavior among specimens featuring canals or pyramidal structures. Specimens with canals exhibit notably lower roll-off angles compared to both flat surfaces and those with pyramidal patterns, leading to a dependence of roll-off angles on the orientation of canals. In humid environments, micromachined specimens exhibit superior water condensation capability compared to untreated SS304 surfaces. Chemically functionalized grooved specimens present larger condensate droplet diameters than flat surfaces. An enhancement in water condensation and a sevenfold higher latent heat transfer coefficient is reported. Specimens with chemical functionalization achieve corrosion protection with an efficiency reaching 82.9%. [ABSTRACT FROM AUTHOR]

Functionalized nano‐SiO2 is an inorganic compound that exhibits hydrophobic properties upon the addition of a silane group through a chemical reaction. This property is highly effective in surface modification for various substrates, including glass, metal, and ceramics. These surface modifications find applications in self‐cleaning, anti‐fogging coatings, and water‐repellent materials. In this work, the role of nano‐SiO2 and Hexadecyltrimethoxysilane (HDTMS) functionalized nano‐SiO2 has been synthesized successfully by the sol–gel method for coating applications. The outcomes of water contact angle (WCA), analysis, Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), scanning electron microscope (SEM), and transmission electron microscope (TEM) observations revealed the successful grafting of hydrophobic long‐chain alkyl groups from HDTMS onto the surface of SiO2 nanoparticles. Notably, when the ratio of SiO2 nanoparticles to HDTMS is 0.25:1, the WCA of the functionalized SiO2 nanoparticles is enhanced significantly. This value is 5.35 times greater than the initial angle of contact before the modification, leading to the achievement of a super hydrophobic property. [ABSTRACT FROM AUTHOR]

The potential application of plasma spraying in the preparation of ceramic electrolyte for porous metal-supported solid oxide fuel cells (SOFCs) is highlighted by its ability to eliminate the need for a high-temperature sintering process. However, the challenge of achieving highly dense electrolytes through plasma spraying remains to be addressed. In this study, a novel electrolyte for porous metal-supported SOFCs (PMS-SOFCs) is developed. This involved the preparation of a highly dense structure of gadolinium-doped ceria (GDC)-lanthanum strontium gallium magnesium oxide (LSGM) composite coating using plasma spraying under atmospheric conditions. The composite electrolyte is prepared using atmospheric plasma spraying (APS). The addition of the low-melting-point LSGM phase enhanced the microstructural densification of the GDC-based composite coating and diminished electron loss in a reducing atmosphere, thereby improving the cell's open-circuit voltage. At 36 kW plasma arc power, the single cell with composite electrolyte exhibited a maximum power density of 371 mw/cm2 at 750 °C and achieved the highest open-circuit voltage (1.03 V) at 600 °C. Moreover, the open-circuit voltage remained stable over a 100-h test. These findings suggest that using APS to deposit a composite electrolyte with added low-melting-point secondary phases presents a promising approach for achieving relatively high OCV in PMS-SOFCs based on cerium oxide electrolytes. [Display omitted] • Bulk-like composite electrolyte directly fabricated by atmospheric plasma spray. • OCV can reach 1.03V at 600 °C for ceria-based composite electrolyte. • LSGM splats effectively blocked the electron conducting in GDC deposits. • Low melting point LSGM could enhance the interface bonding of plasma-sprayed GDC electrolyte. [ABSTRACT FROM AUTHOR]

This article explores the design and optimization of nanodisk metasurfaces for achieving high reflectivity at a defined wavelength. The telecom wavelength of 1550 nm is particularly focused, selected for its potential applications in next‐generation gravitational wave detectors. At this wavelength, the research goes toward the development of thin, low‐loss, high‐reflective coatings, where the metasurface can be chosen as an alternative. An optimization process for the dimensional parameters of nanodisks is proposed based on a systematic tuning approach, which facilitates the realization of various configurations of high‐reflective metasurfaces. The concept of the "magnetic mirror effect" is examined in detail, where the magnetic dipole resonance aligns with the anapole state. Additionally, high reflectivity at the electric dipole resonance ("electric mirror effect") and at the excitation of several multipole moments is explored, including high‐order modes. This variety of configurations affords more flexibility in the phase manipulation of the reflected beam. Furthermore, the potential experimental realization of mirror effects is discussed by exploring the structure in the surrounding medium with a refractive index of nd = 1.4. This research platform provides a promising tool for the fabrication of high‐reflective nanodisk metasurfaces and demonstrates its applicability across various fields. [ABSTRACT FROM AUTHOR]

This work uses the direct current magnetron sputtering (DCMS) of equi-atomic (AlTiZrHfTa) and Si targets in dynamic sweep mode to deposit nano-layered (AlTiZrHfTa)Nx/SiNx refractory high-entropy coatings (RHECs). Transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) are used to investigate the effect of Si addition on the oxidation behavior of the nano-layered coatings. The Si-free nitride coating exhibits FCC structure and columnar morphology, while the Si-doped nitride coatings present a FCC (AlTiZrHfTa)N/amorphous-SiNx nano-layered architecture. The hardness decreases from 24.3 ± 1.0 GPa to 17.5 ± 1.0 GPa because of the nano-layered architecture, whilst Young's modulus reduces from 188.0 ± 1.0 GPa to roughly 162.4 ± 1.0 GPa. By increasing the thickness of the SiNx nano-layer, kp values decrease significantly from 3.36 × 10−8 g2 cm−4 h−1 to 6.06 × 10−9 g2 cm−4 h−1. The activation energy increases from 90.8 kJ·mol−1 for (AlTiZrHfTa)Nx nitride coating to 126.52 kJ·mol−1 for the (AlTiZrHfTa)Nx/SiNx nano-layered coating. The formation of a FCC (AlTiZrHfTa)-Nx/a-SiNx nano-layered architecture results in the improvement of the resistance to oxidation at high temperature. [ABSTRACT FROM AUTHOR]

In this work, optical fiber Bragg grating sensors were used to measure water velocity and examine how it was distributed in open channels. Several types of coatings were incorporated into the design of the sensors to examine their effects on the strain that the fibers experienced as a result of the water flow. Due to their low elastic coefficient, which reduced the hysteresis, the results indicated that the aluminum- and acrylate-coated fibers had the best performance. ANSYS-CFX V2020 R2 software was used to model the strain encountered by the fibers under various flow rates to assess the performance of the FBG sensors. The calculations and actual data exhibited good convergence, demonstrating the accuracy of the FBG sensors in determining water velocity. The study illustrated the usability of the proposal in both scenarios by contrasting its application in rivers and channels. [ABSTRACT FROM AUTHOR]

Passive daytime radiative cooling dissipates heat from surfaces by reflecting sunlight and emitting infrared radiation to the cold outer space, featuring a zero‐energy consumption. Polymer‐dielectric radiative cooling coatings have received significant attention because of their scalable preparation, low cost, and ease of use. However, current dielectric scatterers reveal limited solar reflectance in the polymer‐dielectric coatings due to the optical crowding, which reduces cooling effect and hinders practical application. Employing a scalable emulsion templated method, reversed yolk–shell dielectric scatterers (RYSS) are developed to alleviate optical crowding effects in polymer‐dielectric coatings. This results in coatings with a solar reflectance of ≈97.4% and an infrared emittance of ≈96.9%, while achieving a substantial reduction in scatterers content. Besides, simulation results show that RYSS outperforms core–shell, hollow, and solid scatterers in enhancing solar reflectance. Using phase change materials as emulsion templates, RYSS with high heat storage effectively enhance daytime cooling and reduce nighttime over‐cooling. Moreover, cooling experiments on concentrating photovoltaics demonstrate a temperature drop of 42 °C (≈26.2 times extension of lifetime) and a notable 22% increase in open‐circuit voltage. This work suggests that RYSS presents a promising solution to overcome the challenges of radiative cooling materials and pave the way for their practical applications. [ABSTRACT FROM AUTHOR]

Metal halide perovskite solar cells being one of the fastest emerging technologies for renewable energy still has to become more industry friendly in a way that will allow using it for thin film modules or tandems with conventional silicon devices. The simplest way to achieve this is to use chemical vapor deposition (CVD) technique for tandem production. In this work, we show a method for a single step production of MAPbI3 films in a simple two‐zone CVD reactor from lead diacetate and methyl‐ammonium iodide powders. Obtained films show highly ordered cubic MAPbI3 phase with a thickness of 400–500 nm, good photoluminescence response and absorption band edge similar to spin‐coated film. We used those films to produce p‐i‐n solar cells with ITO/NiO/MAPbI3/C60/Cu structure. The best cell showed negligible 0.23 % PCE right after the manufacturing but significantly improved to 5.5 % PCE after 8 hours of storage in the dark. The main limiting factor affecting the efficiency is low current density, which we attribute to non‐optimized growth conditions; however, our approach is a first step to a single step CVD deposition of MAPbI3 on any type of substrates including texturized silicon subcells for better overall efficiency [ABSTRACT FROM AUTHOR]

Present investigation attempted to explore the tribological properties of atmospheric plasma sprayed coatings. In order to assess the role of solid lubricants, different weight percentages (5, 10, and 15 wt.%) of silver (Ag) were taken, whilst MoS2 concentration remained fixed. Dry sliding wear tests were conducted for different specimens namely, Ni-Al-MoS2-5 wt.% Ag (NA5), Ni-Al-MoS2-10 wt.% Ag (NA10) and Ni-Al-MoS2-15 wt.% Ag (NA15) at different loads of 4, 9, 14 & 19 N, and slid speed of 0.3 m/s under room temperature (RT) conditions. It was observed that coefficient of friction (COF) and wear rate of specimens decreased as the load increased till 14 N, and beyond that increasing trend was noticed. However, the NA10 specimen has revealed the best tribological properties in terms of minimum COF (0.48) and wear rate (4.7 × 10−5 mm3/Nm) at 14 N and 0.3 m/s. The synergy of Ag and MoS2 on the frictional properties of specimens have been well explained with the help of worn surface morphologies and some useful conclusions were made. [ABSTRACT FROM AUTHOR]