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Scheme 1. Schematic diagram of preparation process and reaction mechanism of PFPE and Fc-70. [Display omitted] • 6061 aluminum alloy used in fuel pipelines ensures reliable anti-icing coating test results. • PFPE coating tested on aircraft fuel line to evaluate anti-icing performance under real conditions. • PFPE coating's stability and oil resistance in jet fuel confirmed through rigorous tests. In extreme weather, icing in aircraft fuel systems poses a serious threat to flight safety. Moisture in fuel can freeze inside pipes at high altitudes, risking engine operation and performance. This study explores the use of superhydrophobic technology to prevent icing. Aerospace-grade aluminum alloy (6061) was chemically etched with FeCl 3 to create rough micro and nano structures. The surface was then modified with low surface energy perfluoropolyether (PFPE) to form a superhydrophobic coating. Tests showed that a 1.0 wt% PFPE coating exhibited excellent superhydrophobic and oleophobic properties, with a water contact angle of 154.79° and a jet fuel (RP-3) contact angle of 150.13°. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) analyses confirmed the presence of C-F 3 and C-F 2 bonds. The electrochemical corrosion resistance test shows that the coating has good corrosion resistance and the corrosion resistance rate is 0.61 mm/a. The coating also demonstrated outstanding waterproof performance, resisting grease and stain adhesion under jet fuel immersion. This approach offers a promising solution for surface protection and functional material design. Future research will further optimize its performance and explore broader applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • GO is superior to hydroxylated BN in improving the corrosion resistance. • The external structure of coatings is not changed. • The water diffusion within coatings is more effectively inhibited by GO. The performance of GO and hydroxylated BN in improving the corrosion resistance of a water-borne epoxy coating was comparatively investigated to evaluate the relative excellence of two nanofillers. Electrochemical tests indicated that GO outperformed hydroxylated BN. The corrosion current density was further decreased to 3.48 × 10−6 A/cm2 and polarization resistance was increased to 8.67 × 104 Ω·cm2. The electrochemical reactivity was also most significantly decreased with incorporating GO. Without changing the coating structure, the superior performance of GO was attributed to its exceptional ability to capture water molecules as revealed by simulation results. The mass transfer process of water molecules within coatings was inhibited and the redox reactions during corrosion process were thereby effectively controlled. [ABSTRACT FROM AUTHOR]

[Display omitted] • The surface of the SiO 2 nanoparticles was activated by alumina coating. • The grafting density of SA increased significantly by alumina coating. • The activation mechanism on the alumina-coated particle surface was confirmed. • Provide a new route for green organic modification of SiO 2 nanoparticles. Stearic acid (SA) has a low grafting density on silica nanoparticle (NP) surfaces. However, alumina coating on the particle surface effectively increases the surface reactivity with SA, significantly increasing the grafting density of SA. When the alumina coating amount reaches 15 %, the grafting density of SA increases by 350 % compared to that of the reference sample, while the water contact angle reaches 124°. The coated alumina is chemically bonded to the surfaces of the SiO 2 particles. After alumina coating, the particle surface is loaded with electron acceptor sites with strong electron-receiving ability, allowing SA to undergo Lewis acid–base reactions with the particle surface. [ABSTRACT FROM AUTHOR]

In this study, novel Co-MOFs were synthesized using cobalt nitrate as the metal source and 4,4′-bipyridine as the organic ligand. A one-step solvothermal method was employed to synthesize a black MOFs/LDH composite coating, integrating corrosion resistance, friction reduction, and hydrophobicity into a single coating. [Display omitted] • The Co-MOFs/LDH coating was prepared using a one-step solvothermal method. • The coating exhibits corrosion resistance, superhydrophobicity, and friction reduction functionalities. • Theoretical calculations revealed the binding mechanism between MOFs and LDH. In recent years, metal–organic framework materials (MOFs) have garnered significant attention in the field of metal corrosion protection. In this study, novel Co-MOFs were synthesized using cobalt nitrate as the metal source and 4,4′-bipyridine as the organic ligand. A one-step solvothermal method was employed to synthesize a black MOFs/LDH composite coating, integrating corrosion resistance, friction reduction, and hydrophobicity into a single coating. The successful reaction between metal ions and organic ligands was confirmed through FTIR, FE-SEM, EDX, XRD, and XPS characterization tests. Cross-sectional SEM and EDX analyses demonstrated the successful synthesis of the coating. Electrochemical tests indicated that after 14 days of immersion in 3.5 wt% NaCl, the composite coating exhibited the lowest corrosion current of 2.23 × 10−9 A∙cm−2, outperforming the aluminum substrate (5.99 × 10−6 A∙cm−2) and anodized aluminum (7.08 × 10−7 A∙cm−2). Hydrophobicity tests showed that without additional modification with low surface energy substances, the composite coating had a contact angle of 154.7°, demonstrating excellent hydrophobicity. Tribological tests revealed that the composite coating exhibited superior tribological performance, with a friction coefficient of 0.3. [ABSTRACT FROM AUTHOR]

[Display omitted] • Al-Co-Cr-Fe-Ni coatings were produced by non-vacuum electron beam cladding on steel. • Increase in Al content decreases Fe content transferred from substrate. • Solidus temperatures were assessed by in-situ SXRD to explain different Fe contents. • Solidus temperatures affect the solidification front and grain structure of coatings. • Al 1.5 CoCrFe 0.5 Ni has the highest microhardness and wear resistance. This study investigates the structure and properties of Al-Co-Cr-Fe-Ni high-entropy alloy (HEA) based coatings on steel substrates produced by non-vacuum electron beam cladding. Powder mixtures with Al molar ratios of 0.5, 1, and 1.5 were used for cladding, resulting in coatings with fcc, bcc + fcc, and bcc structures, respectively. The Fe content, which entered the coating from the substrate during cladding, increased from 9.9 up to 48.1 at. % with the decrease of the Al molar fraction from 1.5 to 0.5. In-situ synchrotron X-ray diffraction analysis showed that this effect can be attributed to the higher solidus temperatures of the compositions with higher Al content. Electron backscatter diffraction showed that differences in grain morphology and crystallographic texture were related to the crystallization temperatures in different zones of the coatings. The bcc coating with an Al molar ratio of 1.5 demonstrated superior hardness and wear resistance. Fcc coating, which received more Fe from the substrate, had lower hardness and was prone to plastic flow. However, the specific wear rate of the fcc coating was close to that of the bcc + fcc one due to the hardening of the fcc phase during sliding wear. [ABSTRACT FROM AUTHOR]

[Display omitted] • Li 3 PO 4 coating reduces the air sensitivity of single crystal Ni-rich cathode materials. • Li 3 PO 4 coating and Mg2+ doping inhibited the formation of oxygen vacancies.. • Magnesium ions modulated the structural parameters of the materials and changed the bond lengths. • A simple strategy to enhance the surface stability of single crystal Ni-rich materials is provided. In lithium-ion batteries, Ni-rich single crystal cathode material (Ni > 90 %) is a promising cathode material, but it has not yet been put into commercial application due to defects such as structural degradation, air sensitivity and thermal instability. In this paper, the residual lithium compounds on the surface of high-nickel materials are not useless. Li 3 PO 4 coated and Mg2+ doped single crystal cathode materials (SC-NCM-MP) were successfully prepared by precisely controlling the amount of MgHPO 4 by titration and reacting with lithium compounds left on the surface of LiNi 0.925 Co 0.03 Mn 0.045 O 2 (SC-NCM) cathode materials. The SC-NCM-MP samples exhibit better lattice oxygen stability, Li-ion mobility, storage performance and electrochemical performance, with a retention of 89.36 % after 100 cycles, which is much higher than 79.78 % of SC-NCM. [ABSTRACT FROM AUTHOR]

[Display omitted] • Deposited HEFs showed a higher capacity for HAp formation and bioactivity. • Low working pressure yielded a dense and compact structure with no cracks. • Ti content disparity occurred due to its lower atomic weight during sputtering. • In the dense microstructure, oxygen diffusion through the depth has been minimized. • HEA-1500-Ar25-P0.5 caused robust protection lowering Ni ion release in AS and SBF. This paper presents the experimental findings on the effect of deposition conditions on the microstructure of the corrosion-resistant TiTaNbZrMo high entropy alloy (HEA) thin films deposited on NiTi substrates with the purpose of enhancing biocompatibility of the NiTi shape memory alloy (SMA). For this purpose, RF magnetron sputtering was employed to fabricate TiTaNbZrMo HEA films with 750 nm and 1500 nm thicknesses. Static immersion experiments were conducted in simulated body fluid (SBF) and artificial saliva (AS) solutions for 1, 14, and 28 days to establish the relationship between Ni ion release and deposition parameters. The results revealed that thin films grown under low working pressure exhibited crystalline body-centered cubic (BCC) microstructure with a highly dense, compact, and crack-free structure, while those deposited under high-pressure conditions exhibited an amorphous structure with inherent cracks. The biocorrosion test results indicated that the dense and compact thin film fulfilled the expected corrosion resistance requirements for prolonged utility in human body. Moreover, the HEA films revealed an outstanding amount of hydroxyapatite (HAp) formation, indicating remarkable bioactivity and favorable bone-bonding capabilities. The findings suggest that the HEA films deposited under low working pressures could constitute promising alternatives to conventional coatings on NiTi SMAs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The new TiO 2 /Au/PMMA structure achieves high hardness and excellent transparency. • Robust electromagnetic interference shielding efficiency within the range of 19–29 dB. • The function lead to applications for aerospace equipment and visualization windows. This research addresses the critical need for a highly stable and transparent electromagnetic shielding coating for aircraft PMMA windows and canopies, crucial for safeguarding against electromagnetic interference and enhancing aircraft stealth capabilities. The study presents the novel design, deposition and investigation of transparent coatings, specifically TiO 2 /Au, on PMMA organic glass cockpit canopies. Optimization of TiO 2 and Au film thicknesses is achieved through simulation using TFcalc software, incorporating polarization and optical constants data obtained in this study. The experiments reveal that the deposition of TiO 2 /Au/TiO 2 on PMMA results in fogging, reducing transparency, while novel TiO 2 /Au coating does not exhibit this issue. The TiO 2 /Au configuration, featuring a TiO 2 layer approximately 30 nm thick and an Au film ranging from 11 to 15 nm in thickness, demonstrates outstanding attributes, including a remarkable transparency level of approximately 70–80% and robust electromagnetic interference shielding efficiency within the range of 19–29 dB across S, C, X, and Ku bands of electromagnetic waves. These exceptional performance characteristics position it as an ideal choice for aviation applications. The synergy of the stable Au and durable TiO 2 components, with their high hardness and self-cleaning properties, extends its potential utility to a diverse array of applications. [ABSTRACT FROM AUTHOR]

One-step surface functionalization method utilizing boronic acid grafted polyacrylate (PSA-BA). [Display omitted] • Material-independent method for functionalizing biomaterial surfaces. • Coating with boronic acid-grafted polyacrylate offers multifunctionality to surfaces. • Proof-of-concept studies to demonstrate the potential of polyacrylate-based boronic acid functionalization in the field of biomaterials. • Methodology poised to enhance the biomaterial field by offering a superior alternative for surface functionalization. Most biomaterial surfaces are non-functional, which inevitably requires additional functionalization steps. However, these steps are typically material-dependent; only a few limited methods, such as catechol functionalization using polydopamine coating, have been reported as material-independent for surface modification. In this study, we developed a one-step boronic acid surface functionalization method utilizing a polyacrylate that contains both butyl and boronic acid groups. The butyl group exhibits strong interfacial adhesion due to its low glass transition temperature (T g), which maintains its softness and tackiness, thereby facilitating attachment to various substrates. Meanwhile, the boronic acid acts as a functional group for surface modification. Various substrates, including polymers, metals, and ceramics widely used in implants, were successfully coated with the polyacrylate, bestowing boronic acid functionality on the surface. Given that boronic acid is one of the most widely applied functional groups in the biomaterials field, we anticipate that our methodology will be applicable in developing various biomedical applications such as antifouling coatings, biosensors, and bioadhesives. [ABSTRACT FROM AUTHOR]

[Display omitted] • New synthetic method for phenolic-resin composite with 3D connected BaTiO 3 network. • The effective permittivity of the composite reached to Hashin–Shtrikman upper bound. • An 15.4 % increase in effective permittivity was achieved by only 2.3 vol% of BaTiO 3. • Thermocurable phenolic-resin@BaTiO 3 core–shell particles were used as raw material. • The core–shell particles were prepared by a PLD apparatus equipped with rotary drum. We demonstrate that a 3–0 type bulk composite that reaches the effective permittivity of the Hashin–Shtrikman upper bound can be produced using thermocurable phenolic-resin@BaTiO 3 particles. Core–shell particles with an average shell thickness of 79 nm were prepared using a pulsed laser deposition (PLD) apparatus equipped with a rotary drum. Microstructural analysis revealed that a three-dimensionally connected BaTiO 3 network was constructed in the bulk composite prepared by thermocuring the PLD-processed core–shell powder. Compared with the phenolic resin, the bulk composite containing 2.3 vol% BaTiO 3 showed an 15.4 % increase in effective permittivity; in addition, the dielectric loss and insulation resistance of the composite were not deteriorated. By contrast, a conventional 0–3 type bulk composite, which was composed of randomly dispersed isolated BaTiO 3 particles with an average particle size of 100 nm (similar to the thickness of the shell formed by PLD processing) in a phenolic resin matrix, showed an increase in relative permittivity of only 2.2 %. The results suggest that the proposed process would be an effective method for preparing organic–inorganic bulk composites with the 3–0 type structure with various enhanced physical properties (including relative permittivity) that follow the additive law. [ABSTRACT FROM AUTHOR]

Epoxy composite coatings reinforced with different contents of reduced graphene oxide (RGO) nanosheets were prepared on N80 substrate. The aim of this work is to identify the applicability of RGO modified epoxy coatings on N80 tubing in oil and gas production environments with high temperature and high salinity. Transmission electron microscopy, selected area electron diffraction and scanning electron microscopy were employed to characterize the RGO and coatings. The adhesion, toughness and corrosion resistance of epoxy composite coatings were investigated. It indicated that the proper addition of RGO nanosheets effectively reduced the number and size of pores in the epoxy composite coatings, and improved the adhesion, toughness, corrosion resistance of the epoxy composite coatings. The epoxy composite coating with 1.0 wt% RGO displayed the best anti-corrosion performance in 10.0 wt% NaCl solution. Unlabelled Image • Addition of RGO effectively improved the adhesion and toughness of epoxy coatings. • Addition of RGO effectively reduced the number and the size of pores in coatings. • Addition of RGO effectively improved the corrosion resistance of epoxy coatings. • Epoxy coatings with 1.0 wt% RGO displayed the best anti-corrosion performance. [ABSTRACT FROM AUTHOR]

In this work, a conversion coating of phytic acid (PA)/calcium ion (Ca2+) was prepared on a magnesium-strontium (Mg-Sr) alloy surface through a layer-by-layer self-assembly method. The effect of the pH value on the corrosion resistance of coatings was studied systematically. The addition of a Ca2+ could enhance the intermolecular chelation of PA and repair the defects of the coating itself. The results of electrochemical and immersion testing confirmed that a PA/Ca2+ conversion coating could adjust the corrosion rate of Mg-Sr alloys. Compared to a bare Mg-Sr alloy, the corrosion current density of Mg&OH&PA(5.5)&Ca2+ was decreased by about three orders (2.726 × 10−4 A/cm2 to 4.304 × 10−7 A/cm2). In vitro tests showed that a Ca2+ in the coatings could not only promote the formation of apatite, but also favored osteoblast proliferation. In addition, this conversion coating could significantly enhance the expression of alkaline phosphatase activity by 50–60% compared to a bare Mg-Sr alloy. • Layer-By-Layer self-assembly technique repairs the defects of the pure phytic acid coating. • Phytic acid/Ca conversion coating endows Mg-Sr alloy with controllable corrosion rate. • Phytic acid/Ca conversion coating of Mg-Sr alloy brings excellent osteoinductivity. • Providing broad application prospect for magnesium-based scaffolds and implants. [ABSTRACT FROM AUTHOR]

An alumina coating with a thickness of 20–50 μm was deposited by plasma electrolytic oxidation (PEO) on an AA 7075 Al alloy in an alkali-aluminate electrolyte using a 5 kW DC power supply. After the formation of the coating, the effects of current density, electrolyte concentration, and process time on the coating characteristics were investigated comprehensively. In order to achieve improved tribological and corrosion properties, the prepared samples were evaluated by means of various characterization techniques including scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses, micro-hardness, thickness and roughness measurements, corrosion potentio-dynamic, and pin-on-disk wear tests. Electrophoretic graphite absorption was subsequently carried out on the samples, which resulted in the desirable experimental results to boost the coating in terms of roughness, tribological, and corrosion properties. The positive effects of graphite absorption on the PEO coatings were also elaborated in detail. Unlabelled Image • Obtaining the optimized PEO coating parameters on an AA 7075 Al alloy • Probing the corrosion and pin-on-disk wear properties of PEO coatings • Studying the graphite absorption mechanism and its effects on the performance of coatings [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Surface-modified method was applied to fabricate graphene-based silk fabric. • The modified silk fabric exhibited excellent flame retardant properties. • The UPF value of modified silk fabric reached 50+. Abstract Environmentally-friendly flame retardant silk fabrics were successfully fabricated by an industrialized surface modification method. The coating-reduction process was rationally designed and repeated several cycles to deposit more amounts of reduced graphene oxide (rGO) sheets on silk fabric surface for better flame retardant performance of the prepared fabric. The prepared rGO-coated silk fabric (rGOSF), especially the silk fabric after 9 cycles of coating-reduction process showed improved flame retardant performance compared with pristine silk fabric, as evidenced by higher limiting oxygen index value, better thermal stability and shorter damaged length in vertical flame test. Moreover, smoke density test demonstrated the prepared rGOSF also had excellent smoke suppression property. In addition, the UPF value of rGOSF can also be increased to 55.19 (50+). Mechanical properties tests indicated the used surface modification method had no effect on the tensile strength of rGOSF. Moreover, washing durability test showed the prepared rGOSF had good fastness to washing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ti 3 C 2 T x was stably doped in PPy coating as a conductive additive. • Composite coating of novel 3D closed vesicle structure yielded robust barrier effect. • Ti 3 C 2 T x endowed composite coating with enduring electroactivity and strong adhesion on copper. • Composite coating offered long-term protection for electronic devices. A closed 3D vesicle polypyrrole-based composite coating (PPy-STi) was electropolymerized on copper with the support of sodium dodecyl sulfate (SDS)-stabilized Ti 3 C 2 T x -MXene via an inverted-electrode cyclic voltammetry route. Due to the promoted polymer nucleation effect of SDS and active catalysis of hydrogen evolution by well-dispersed Ti 3 C 2 T x , a unique vesicle-like architecture of PPy-STi were formed with twisted diffusion pathways, which endowed a strong barrier against aggressive species. Meanwhile the stabilized Ti 3 C 2 T x with high metallic conductivity facilitated the overall electroactivity of PPy-STi coating, yielding much improved anodic protection for copper in artificial seawater (ASW). Relying on the tolerant physical barrier and robust anodic protection capacity of PPy-STi, the coated copper could sustain its passivated state during 10 days of immersion in ASW. The integration of MXenes in conductive polymer coating with enhanced protection characteristics may provide a new strategy to improve the corrosion resistance of electronic devices in the harsh environment. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A discontonuous 3-step dip-coating process of silicone tubes allows for a uniform coating. • A controled release of the polysaccharide-based coatings is observed during one week. • The polysaccharide-based coatings are stable against mechanical abrasion. • The polysaccharide based coatings are antimicrobial and reduce biofilm formation. Abstract In this work, surfaces of casted silicone sheets and silicone tubes were functionalized with colloidal polysaccharide complexes (chitosan, carboxymethyl chitosan, and hyaluronic acid in combination with a lysine-based surfactant) in order to introduce antimicrobial and antifouling surface properties. The surface chemistry and morphology, as well as the chemical and mechanical stability of the coatings were characterized. For this purpose, different microscopic and spectroscopic methods, pH-potentiometric titrations and standard methods for evaluation of mechanical properties were used. Finally, the antimicrobial and antifouling properties of functionalized silicone materials were evaluated in vitro. The findings of the physicochemical characterization showed that a discontinuous 3-step dip-coating process can be successfully implemented to coat casted polydimethylsiloxane sheets and tubes with colloidal polysaccharide complexes. These coatings exhibit slow-release leaching in aqueous environment at pH 4.5, 7, and 8 and show very good stability against mechanical abrasion, thus displaying high stability potential during catheter insertion. The antimicrobial properties against gram-positive bacteria, gram-negative bacteria and fungi, showed inhibition of bacterial growth of up to 86%. Furthermore, the bacterial biofilm formation tests have revealed that the hyaluronic acid-surfactant coating exhibits high biofilm growth reduction. [ABSTRACT FROM AUTHOR]

In this study the influence of nanoscale Y 2 O 3 particles on structural, morphological, mechanical and the elemental composition of Ni-P coatings have been investigated using scanning electron microscopy (SEM), microhardness, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and atomic force microscopy (AFM). Electrodeposition process was implemented to develop a new Ni-P-Y 2 O 3 nanocomposite coatings using different concentrations of Y 2 O 3 of 0.25, 0.50, 0.75, and 1.00 g/L. The surface analysis exhibits the formation of intact, homogenous and dense coatings of the nodular structure without observable surface defects such as pores and cracks. The mechanical properties were improved by the incorporation of hard Y 2 O 3 nanoparticles. The corrosion protection of the as-prepared Ni-P coatings before and after addition of Y 2 O 3 nanoparticles was evaluated using different electrochemical techniques in 3.5 wt.% NaCl. The results revealed that Ni-P-1.00 g/L Y 2 O 3 metallic coating posses the highest corrosion protection efficiency (PE), of 90%. [ABSTRACT FROM AUTHOR]

A (polyvinylpyrrolidone (PVP)/deoxyribonucleic acid (DNA)) n coating was fabricated via layer-by-layer (LbL) assembly dip coating method. The surface morphologies, chemical compositions and corrosion resistances of the coatings were investigated using field-emission scanning electron microscopy, X-ray photoelectron spectrometer, Fourier transform infrared, X-ray diffractometer and electrochemical and hydrogen evolution measurements. The results indicated that the (PVP/DNA) n coating shows a smooth surface with shallow scratches and some corrosion cracks, which possesses a good corrosion resistance in simulated body fluid, especially for n  = 20. The (PVP/DNA) n coating can be used as a inducer to construct a biomimetic biocompatible Ca-P coating on Mg alloys. Additionally, we suggest and discuss a corrosion mechanism for the coating. [ABSTRACT FROM AUTHOR]

In the article, the interaction between low rank coal (LRC) and kaolinite particles was studied using density functional theory (DFT) calculations to interpret the mechanisms of kaolinite coating on LRC flotation. Four representative model molecules with different polarities in LRC, namely, benzoic acid, phenol, benzene and toluene, were taken into account in analyzing the interactions with kaolinite surfaces. The calculated results of adsorption configuration and bonding demonstrate that the interaction of LRC model molecules and kaolinite is the result of the joint actions of benzene rings and oxygen-containing groups. By analyzing adsorption energy, density of state (DOS) and charge transfer, it could be deduced that whether the (0 0 1) or the (0 0  1 ¯ ) surface of kaolinite, van der Waals attraction governs their interaction with LRC model molecules. It also could be concluded that LRC model molecules are more inclined to adsorb on the (0 0 1) surface in comparison with the (0 0  1 ¯ ) surface. However, due to the strong adsorption between the water molecule and the kaolinite (0 0 1) surface, it should be difficult to replace the adsorbed water molecules on the (0 0 1) surface for LRC model molecules. Therefore, the van der Waals attraction between the LRC model molecules and the kaolinite (0 0  1 ¯ ) surface is responsible for the kaolinite coating on LRC flotation. The available literature is in accord with our results. [ABSTRACT FROM AUTHOR]

In this work, Cu atoms and Al 2 O 3 nanoparticles were simultaneously incorporated into a Ni coating during an electrodeposition process to produce Ni-Cu/Al 2 O 3 nano-composite coatings. Then, the effect of the additions of the Cu and Al 2 O 3 species on some properties of these coatings was investigated. X-ray diffraction and scanning electron microscopy equipped with energy dispersive X-ray spectroscopy were employed for the structural characterization of the products. The mechanical properties of the deposited coatings were also investigated by Vickers microhardness and pin-on-disc wear testing. Also, the corrosion behavior of the produced coatings was investigated in a NaCl solution. Results showed that the addition of Cu atoms and Al 2 O 3 nanoparticles changes the texture of the pure Ni coating and decreases the crystallite size from 91 nm for pure Ni to 16 nm for Ni-Cu/Al 2 O 3 (20 g/L) nano-composite coating. It was also found that the microhardness, wear resistance, and corrosion resistance of the deposited coatings are increased by the incorporation of Cu atoms and Al 2 O 3 nanoparticles in the Ni coating. Typically, the microhardness and wear resistance are increased about 2.4 and 3.75 times, respectively. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the oxidation properties of amorphous aluminum phosphate coating. Aluminum phosphate precursor solution was prepared by a sol–gel process and then applied on AISI 304 stainless steel using dip coating technique. To evaluate the oxidation behavior, samples were placed in an electrical furnace upto 1100 °C for 100 h in air with weight measurements performed at regular ten-hour intervals. Phase composition analysis of the coatings before and after cyclic oxidation process were performed by X-ray diffractometer (XRD). The surface and cross-sectional morphology of the coatings were observed using scanning electron microscopy (SEM) analysis equipped with energy dispersive spectroscopy of characteristic X-rays (EDS). The amorphous-nanocrystalline structure and distribution of nanocrystals in the amorphous matrix were studied by transition electron microscopy (TEM). According to SEM images a uniform, continuous and crack-free coating was achieved. XRD analysis as well as TEM observations showed that the amorphous structure of coating remained unchanged after annealing at 500 °C for 15 min however; an amorphous-nanocrystalline structure was obtained after annealing at 1100 °C for 1 h. Weight change measurements after 100 h oxidation test revealed that the trace of weight gain against oxidation time for both coated and un-coated substrates were parabola in nature and the range of the weight change of the bare substrate was about 30 times greater than that of observed for the aluminum phosphate coating. In general, the results showed that the synthesized amorphous aluminum phosphate is capable of surface protecting of metals/alloys against degradation at harsh environments. [ABSTRACT FROM AUTHOR]

In this work, polyetherimide (PEI) nanoparticles were prepared on carbon fiber (CF) surfaces via an evaporation-induced surface modification method. Scanning electron microscopy analysis revealed that the average diameter of the PEI nanoparticles linearly increased with increasing PEI concentration. This finding indicated that the nanoparticle size on the CF surface could be controlled by changing the PEI concentration used in the surface modification process. The possible formation mechanism of the PEI nanoparticles on the CF surfaces was also investigated by cross-section observation of CF using field-emission scanning electron microscopy (FE-SEM). In addition, the single fiber strength and interfacial shear strength between the CFs and epoxy resin were observed to increase after the surface modification. The interfacial shear strength (IFSS) results between treated CF before and after heating show that the presence of PEI nanoparticles had a great influence on IFSS. At a PEI concentration of 0.2%, the IFSS value reached its maximum value, 44.02% more than that of desized CF. [ABSTRACT FROM AUTHOR]

Oxidation resistance of TiC–SKD11 composite has been improved through SiC/TiB 2 based hybrid coating by a simple air spray process and subsequent transition to dense and stable phases in oxidation environment. As a result of the oxidation test at 700 °C for up to 50 h, the coated TiC–SKD11 composite exhibited excellent oxidation resistance characteristics compared with the uncoated TiC–SKD11 composite, and also compared to SUS431 and 17-4PH. The formation of a thermally stable, volume-expanded SiO 2 and TiO 2 coating layer with the aid of B 2 O 3 by phase transition of TiB 2 /SiC based hybrid coating under oxidation atmosphere is the origin of the improved anti-oxidation ability of the TiC–SKD11 composite. [ABSTRACT FROM AUTHOR]

This work deals with the features of the structure of combined ZrC/Ni-ultradisperse diamonds (UDD) coating synthesized by electroplating and cathode arc evaporation physical vapor deposition (CAE-PVD) techniques on the tungsten carbide WC – 2 wt% Co on cutting inserts to improve tool life. The microstructure, phase composition, and micro-scratch test analysis of the ZrC/Ni-UDD coating were studied. The ZrC/Ni-UDD coating consists of separate phases of zirconium carbide ZrC, α-Ni, and Ni-UDD phase. The surface morphology of the coating shows a pattern with pits, pores, and particles. Separated nanodiamond particles are present in the pores of the combined coating. Therefore, the structure of the bottom layer of Ni-UDD affects the morphology of the surface of the ZrC/Ni-UDD coating. The obtained value of the critical loads on the scratch track of the coating in 26 N proves a sufficiently high value of the adhesion strength of the intermediate Ni-UDD-layer with hard alloy of WC-Co substrate. Due to their unique structure ZrC/Ni-UDD-coatings can be used to increase the durability period of a wood-cutting milling tool for cutting chipboard by CNC machines. [ABSTRACT FROM AUTHOR]

Experimental investigation was performed to highlight the influence of ionic bounding and surface roughness effects on the surface wettability. Nanocoating technique via e-beam physical vapor deposition process was used to fabricate aluminium (Al) film of 50, 100, and 150 nm on the surface of an Al substrate. Microstructures of the samples before and after deposition were observed using an atomic force microscopy. A goniometer device was later on used to examine the influence of surface topography on deionised water of pH 4, 7 and 9 droplets at a temperature ranging from 10 °C to 60 °C through their contact angles with the substrate surface, for both coated and uncoated samples. It was found that, although the coated layer has reduced the mean surface roughness of the sample from 10.7 nm to 4.23 nm, by filling part of the microstructure gaps with Al nanoparticles, the wettability is believed to be effected by the ionic bounds between the surface and the free anions in the fluid. As the deionised water of pH 4, and 9 gave an increase in the average contact angles with the increase of the coated layer thickness. On the other hand, the deionised water of pH 7 has showed a negative relation with the film thickness, where the contact angle reduced as the thickness of the coated layer was increased. The results from the aforementioned approach had showed that nanocoating can endorse the hydrophobicity (unwitting) nature of the surface when associated with free ions hosted by the liquid. [ABSTRACT FROM AUTHOR]

In the present work, we report one-step immobilization of nano-heparin coating on PLA membranes via initiated chemical vapor deposition (iCVD) for enhanced hemocompatibility. The nano-coating introduced onto the membrane surface via the crosslinking of P(MAA-EGDA) was confirmed by the FTIR, SEM and weight measurement respectively. The negative carboxyl groups could form the hydration interaction with the protein and platelets and electrostatic interaction with amide groups of thrombin by the mediation of antithrombin, which is similar but different with heparin. The P(MAA-EGDA) coated membranes showed suppressed platelet adhesion and prolonged clotting time (APTTs increased to 59 s, PTs increased to 20.4 s, TTs increased to 17.5 s, and the FIBs declined by 30 mg/dL). Moreover, the complement activation tests demonstrated the formation of C3a and C5a was inhibited. All results demonstrated that the nano-coating of P(MAA-EGDA) via iCVD significantly enhanced the hemocompatibility of PLA membranes, which is also applicable for various membranes. [ABSTRACT FROM AUTHOR]

A series of thin-film composite reverse osmosis membranes based on polyamide have been modified by coating the polyvinyl alcohol and 3-mercaptopropyltriethoxysilane aqueous solution prepared by a sol-gel process on the membrane surface, followed by thermal crosslinking treatment. In order to improve the hydrophilicity of the modified TFC membranes, the membranes were then immersed into H 2 O 2 aqueous solution to convert −SH into −SO 3 H. The resulting TFC membranes were characterized by SEM, AFM, ATR-FTIR, streaming potential, XPS as well as static contact angle. After surface modification with the organic-inorganic hybrid material, the TFC membranes show increased NaCl rejection and decreased water flux with increasing 3-mercaptopropyltrimethoxysilane content in coating solution. The optimal modification membrane (PA-SMPTES-0.8) exhibits a NaCl rejection of 99.29%, higher than that (97.20%) of the virgin PA membrane, and a comparable water flux to virgin PA membrane (41.7 L/m 2 h vs 47.9 L/m 2 h). More importantly, PA-SMPTES-0.8 membrane shows much more improved fouling resistance to BSA than virgin PA and PVA modified PA (PA-PVA-1.0) membranes. PA-SMPTES-0.8 membrane loses about 13% of the initial flux after BSA fouling for 12 h, which is lower than that of virgin PA and PA-PVA-1.0 membranes (42% and 18%). Furthermore, the flux recovery of PA-SMPTES-0.8 membrane reaches 94% after cleaning. Thus the TFC membranes modified by this organic-inorganic hybrid technology show potential applications as antifouling RO membrane for desalination and purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Submicron TiC particles reinforced Inconel 718 coatings were prepared. • TiC addition changed the morphology of Inconel 718 and reduced segregation. • TiC consists of unmelted and newly solidified parts. • High hardness and wear resistance were obtained. Submicron TiC particles reinforced Inconel 718 coatings were prepared by laser cladding. The coatings have a dense microstructure, uniformly distributed TiC particles, and good metallurgical bonding to the substrates. TiC particles serve as the crystal nucleus for alloy solidification, and the alloy solidifies into an equiaxed grain structure, reducing element segregation during the solidification process. The TiC morphology changes from a petal-like structure to nearly spherical particles as the TiC content increases from 10 wt% to 50 wt%. The spherical TiC particles grow based on the unmelted TiC nuclei when TiC content is 50 wt%, and these TiC particles consist of unmelted TiC and newly solidified Ti(Nb, Mo, Cr)C. The coating hardness slightly decreases and then increases with TiC increasing from 0 wt% to 50 wt%, and the wear resistance increases with increasing TiC content. [ABSTRACT FROM AUTHOR]

Here we report a novel transitional metal oxide (NiCo 2 O 4 ) coated Li[Ni 0.03 Mn 1.97 ]O 4 micro-/nano- spheres as high-performance Li-ion battery cathode material. A thin layer of ∼10 nm NiCo 2 O 4 was formed by simple wet-chemistry approach adjacent to the surface of Li[Ni 0.03 Mn 1.97 ]O 4 micro-/nano- spheres, leading to significantly enhanced battery electrochemical performance. The optimized sample(1 wt%) not only delivers excellent discharge capacity and cycling stability improvement at both room temperature and elevated temperatures, but also effectively prevents Mn dissolution while retaining its coating structure intact according to XRF and TEM results. The CV and EIS break-down analysis indicated a much faster electrochemical reaction kinetics, more reversible electrode process and greatly reduced charge transfer and Warburg resistance, clearly illustrating the dual role of NiCo 2 O 4 coating to boost electron transport and Li + diffusion, and alleviation of manganese dissolving. This approach may render as an efficient technique to realize high-performance lithium ion battery cathode material. [ABSTRACT FROM AUTHOR]

The structure and the corrosion behaviour in the Ringer's solution of Co-Mo/TiO 2 nano-composite coatings have been investigated. They consist of aggregates of TiO 2 nanoparticles uniformly distributed in a Co-Mo alloy matrix (crystallite size of about 2 nm). Both nodular (thickness less than 20 μm) and globular structures (thickness greater than 20 μm) have been observed using field-emission scanning electron microscopy. Under potentiostatic control (in Ringer's solution), oxidation of the coating first occurs followed by (with increasing applied potential) both oxidation and selective dissolution of Co. At the OCP value, Co is oxidized in the form of Co 2+ -based compounds (CoO, Co(OH) 2 or α-CoMoO 4 ) in the coating. This process only occurs in the outermost part of the coating. Therefore, the bulk properties of the coating are not affected after long-term ageing in the Ringer's solution at OCP. [ABSTRACT FROM AUTHOR]

Sulfonated polyvinyl alcohol (SPVA) was synthesized by esterification reaction of PVA and sulfuric acid, and the structure was characterized by FTIR spectrum. Then a series of TFC membranes modified with cross-linked SPVA layer were fabricated by coating method, with glutaraldehyde as the cross-linker. The resulting TFC membranes were characterized by SEM, AFM, ATR-FTIR, XPS, streaming potential as well as static contact angle. The TFC membranes modified with SPVA exhibit decreased water flux and increased NaCl rejection with SPVA content increasing in the coating aqueous solution. The optimal PA-SPVA-0.5 sample exhibits a NaCl rejection of 99.18%, which is higher than the 98.32% of the virgin PA membrane. More importantly, the PA-SPVA-0.5 membrane shows much more improved fouling resistance to BSA and CTAB than virgin PA membrane and the TFC sample modified with PVA (PA-PVA-0.5). PA-SPVA-0.5 membrane loses about 8% of the initial flux after BSA fouling for 12 h, which is much lower than those of virgin PA and PA-PVA-0.5 membranes (28% and 15%, respectively). Furthermore, the flux recovery of the PA-SPVA-0.5 membrane reaches above 95% after cleaning. Thus, the PA-SPVA-0.5 membrane shows potential applications as antifouling RO membrane for desalination and purification. [ABSTRACT FROM AUTHOR]

A γ-(2,3-epoxypropoxy) propyltrimethoxysilane/graphene (GPTMS/rGO) coating on AA-2024 aluminum alloy was prepared by immersing the aluminum alloy sample in a silane/graphene oxide solution and curing in oven at 180 °C. Silanol groups were grafted onto graphene oxide sheets during hydrolysis. The graphene oxide was stacked layer by layer through silanol groups. The synthesized coating was characterized with Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectra and scanning electron microscopy. The thickness of the composite coating increased greatly compared with that of silane coating, due to the mutual riveting effect. The covalent metallic-siloxane bonds (AlOSi) improved the adhesion force greatly. The laminate structure of graphene increased the hardness and declined the brittleness over 200 °C. The GPTMS/rGO coating showed good corrosion resistance. In 3.5% NaCl solution the anodic current density of the aluminum alloy sample with GPTMS/rGO coating was reduced by several orders of magnitude compared with those of bare aluminum alloy or the sample with graphene film. [ABSTRACT FROM AUTHOR]

This study presents the sensing studies of QCM sensors which coated with calix[4]arene derivatives bearing different functional groups towards some selected Volatile Organic Compounds (VOCs). Initial experiments revealed that QCM sensor coated with calix -3 bearing bromopropyl functionalities was relatively more effective sensor for methylene chloride (MC) emissions than the other calix[4]arene coated QCM sensors, in aqueous media. In further experiments, this effective calix -3 coated QCM sensor were used in detailed sensing studies of selected VOCs. However, the results demonstrated that calix- 3 coated QCM sensor was most useful sensor for toluene (TOL) emissions among all. Moreover, the sensing of TOLs with calix- 3 coated QCM sensor was also evaluated in terms of sorption phenomena. Consequently, calix- 3 coated QCM sensor was good sensor for TOL emissions, and thus it demonstrated that the coating of QCM sensor surface with calixarenes was good approach for sensing of the VOCs. [ABSTRACT FROM AUTHOR]

Nanostructured ceria-based coatings are shown to be protective against high-temperature oxidation of AISI 304 due to the dynamics of oxidation state and associated defects. However, the processing parameters of deposition have a strong influence in determining the structural and morphological aspects of ceria. The present work focuses on the effect of variation in substrate temperature (50–300 °C) and deposition rate (0.1–50 Å/s) of ceria in electron beam physical vapour evaporation method and correlates the changes in structure and morphology to high-temperature oxidation protection. Unlike deposition rate, substrate temperature exhibited a profound influence on crystallite size (7–18 nm) and oxygen vacancy concentration. Upon isothermal oxidation at 1243 K for 24 h, bare AISI 304 exhibited a linear mass gain with a rate constant of 3.0 ± 0.03 × 10 −3 kg 2 m −4 s −1 while ceria coating lowered the kinetics by 3–4 orders. Though the thickness of the coating was kept constant at 2 μm, higher deposition rate offered one order lower protection due to the porous nature of the coating. Variation in the substrate temperature modulated the porosity as well as oxygen vacancy concentration and displayed the best protection for coatings deposited at moderate substrate temperature. The present work demonstrates the significance of selecting appropriate processing parameters to obtain the required morphology for efficient high-temperature oxidation protection. [ABSTRACT FROM AUTHOR]

A comparative study of the wetting of three different commercial polymer melts on various coated and uncoated steel surfaces is described in this report. The wettability of steel and coatings (three different titanium nitride coatings, TiN, TiNO x , TiNO y, a chromium coating, CrN, and a diamond-like carbon coating, DLC) used for mold in polymer processing is determined at different temperatures between 25 °C and 120 °C. Contact angle measurements of melted polypropylene (PP), Acrylonitrile Butadiene Styrene (ABS) and Polycarbonate (PC) on steel and on the different coatings were performed to investigate the wetting behavior under closer-to-processing conditions. Recommendations for good measurement conditions were proposed. Moreover, the surface free energy of each melt polymer was determined. The works of adhesion between all polymers and all substrates were established. Among all tested polymers, the lowest value of the works of adhesion is calculated for ABS and for PC thereafter, and the highest value is calculated for PP. These results will be particularly important for such applications as determining the extent to which these polymers can contribute to the replication quality in injection molding. [ABSTRACT FROM AUTHOR]

A novel immobilized solid acid coating on Q235 carbon steel was successfully prepared via plasma electrolytic oxidation. Sulfate functionalized Fe 3 O 4 /FeAl 2 O 4 was confirmed by XRD, TEM and XPS analysis and surface acidic property was verified by NH 3 -TPD measurement. Fenton-like degradation performance was evaluated by employing phenol as target pollutant. Fast phenol degradation under the wide range of pH (pH 6–9) was accomplished within only 11 min. Without sulfate functionalization, phenol could hardly be degraded by Fenton-like oxidation which meant that after sulfate functionalization the existence of acidic microenvironment on the catalyst surface not only provided an optimal circumstance for enhanced Fenton-like reaction, but also avoided adjusting pH of the treated wastewater. A reasonable Fenton-like degradation mechanism was proposed. This paper offered a novel design thought for synthesizing excellent Fenton-like coating catalyst under circumneutral pH. [ABSTRACT FROM AUTHOR]

p- and n-type bismuth telluride thin films have been synthesized by using a combinatorial sputter coating system (COSCOS). The crystal structure and crystal preferred orientation of the thin films were changed by controlling the coating condition of the radio frequency (RF) power during the sputter coating. As a result, the p- and n-type films and their dimensionless figure of merit (ZT) were optimized by the technique. The properties of the thin films such as the crystal structure, crystal preferred orientation, material composition and surface morphology were analyzed by X-ray diffraction, energy-dispersive X-ray spectroscopy and atomic force microscopy. Also, the thermoelectric properties of the Seebeck coefficient, electrical conductivity and thermal conductivity were measured. ZT for n- and p-type bismuth telluride thin films was found to be 0.27 and 0.40 at RF powers of 90 and 120 W, respectively. The proposed technology can be used to fabricate thermoelectric p–n modules of bismuth telluride without any doping process. [ABSTRACT FROM AUTHOR]

Titanium dioxide was incorporated into chemically-bonded phosphate ceramic for use as photocatalytic inorganic coating. The coatings obtained were applied to unglazed ceramic tiles and cured at 350 °C. The surfaces were characterized by photocatalytic activity, determined in aqueous medium, based on the degradation of methylene blue dye. The effects of the percentage of TiO 2 and the thickness of the layer on the photocatalytic efficiency were evaluated. The influence of the incorporation of TiO 2 on the consolidation of the phosphate matrix coating was investigated using the wear resistance test. The crystalline phases of the coatings obtained were determined by XRD. The microstructure of the surfaces was analyzed by SEM. The thermal curing treatment did not cause a phase transition from anatase to rutile. An increase in the photocatalytic activity of the coating was observed with an increase in the TiO 2 content. The dye degradation indices ranged from 14.9 to 44.0%. The photocatalytic efficiency was not correlated with the thickness of the coating layer deposited. The resistance to wear decreased with an increase in the TiO 2 content. Comparison with a commercial photocatalytic ceramic coating indicated that there is a range of values for the TiO 2 contents which offer potential for photocatalytic applications. [ABSTRACT FROM AUTHOR]

LiNiO 2 -based layered oxides are of great importance as cathode materials for rechargeable batteries. In this paper, illustrating LiNi 0.8 Co 0.15 Al 0.05 O 2 as an example, the effect of nanoscale MnCO 3 treatment on LiNiO 2 -based materials is investigated for the first time. The structures of materials and the properties about the object surface are characterized by XRD, SEM, TEM, EDAX and XPS. The results demonstrate that a part of MnCO 3 is able to react with lithium impurities to form nonstoichiometric Li x Mn y O 4 and the rest of MnCO 3 is converted to MnO 2 coating on the surface of the material in situ. After 100 repeated cycles at 1C, the modified material exhibits a capacity retention rate of 91.2%, while the bare material only remains 84.8%. And the modified material exhibits more significantly improved cycling stability when cycling at 60 °C, maintaining 85.7% of its initial capacity at 1C after 100th cycles. The consumption of Li impurities can decelerate the decomposition of electrolyte during cycling, thus result in less resistive byproducts. Moreover, the obtained MnO 2 coating layer acts as an isolating layer to suppress the drastic reaction between active material and electrolyte. This synergistic effect is responsible for the excellent properties of MnCO 3 -modified material. [ABSTRACT FROM AUTHOR]

TiNi/Ti 2 Ni matrix composite coatings were produced on Ti6Al4V surfaces by laser cladding the mixed powders of Ni-based alloy and different contents of TaC (0, 5, 10, 15, 20, 30 and 40 wt.%). Microstructures of the coatings were investigated. High-temperature wear tests of the substrate and the coatings were carried out at 600 °C in air for 30 min. High-temperature oxidation tests of the substrate and the coatings were performed at 1000 °C in air for 50 h. Wear and oxidation mechanisms were revealed in detail. The results showed that TiNi/Ti 2 Ni as the matrix and TiC/TiB 2 /TiB as the reinforcements are the main phases of the coatings. The friction coefficients of the substrate and the coatings with different contents of TaC were 0.431 (the substrate), 0.554 (0 wt.%), 0.486 (5 wt.%), 0.457 (10 wt.%), 0.458 (15 wt.%), 0.507 (20 wt.%), 0.462 (30 wt.%) and 0.488 (40 wt.%). The wear rates of the coatings were decreased by almost 83%-98% than that of the substrate and presented a decreasing tendency with increasing TaC content. The wear mechanism of the substrate was a combination of serious oxidation, micro-cutting and brittle debonding. For the coatings, oxidation and slight scratching were predominant during wear, accompanied by slight brittle debonding in partial zones. With the increase in content of TaC, the oxidation film better shielded the coatings from destruction due to the effective friction-reducing role of Ta 2 O 5 . The oxidation rates of the substrate and the coatings with different contents of TaC at 1000 °C were 12.170 (the substrate), 5.886 (0 wt.%), 4.937 (5 wt.%), 4.517 (10 wt.%), 4.394 (15 wt.%), 3.951 (20 wt.%), 4.239 (30 wt.%) and 3.530 (40 wt.%) mg 2 cm −4 h −1 , respectively. The oxidation film formed outside the coating without adding TaC was composed of TiO 2 , NiO, Cr 2 O 3 , Al 2 O 3 and SiO 2 . When TaC was added, Ta 2 O 5 and TaC were also detected, which effectively improved the oxidation resistance of the coatings. The addition of TaC contributed to the improvement in high-temperature wear and oxidation resistance. [ABSTRACT FROM AUTHOR]

In order to prevent freshwater biofouling glass and metal surfaces were coated with novel transparent methacrylate-based copolymers. The multifunctionality of the copolymers, such as adhesion to the substrate, surface polarity, mechanical long-term stability in water, and ability to form metal complexes was inserted by the choice of suitable comonomers. The monomer 2-acetoacetoxy ethyl methacrylate (AAMA) was used as complexing unit to produce copper(II) complexes in the coating’s upper surface layer. The semifluorinated monomer 1H,1H,2H,2H- perfluorodecyl methacrylate was employed to adjust the surface polarity and wettability. Comprehensive surface characterization techniques, such as X-ray photoelectron spectroscopy (XPS) and contact angle measurements showed that surface compositions and properties can be easily adjusted by varying the concentrations of the comonomers. The formation of copper(II) complexes along the copolymer chains and their stability against washing out with plenty of water was proven by XPS. Copolymers containing semifluorinated comonomers significantly inhibited the growth of Achnanthidium species. Copolymers with copper-loaded AAMA-sequences were able to reduce both the growth of Achnanthidium spec. and Staphylococcus aureus . [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual-functional coatings based on curcumin and APEG were prepared. • The coatings exhibited excellent antibacterial and antibiofilm properties. • The coatings reduced protein and platelet adhesion significantly. • The coatings exhibited excellent non-hemolysis and cytocompatibility. • The coatings have promising potential for the prevention of implant infections. Infection associated with implants and devices is a problem in medicine, especially when bacterial colonization leads to the formation of biofilms on the implant surface. Here, we report an effective strategy to develop dual-functional coatings on titanium implants with antibacterial and antifouling properties to combat biofilm infections. Coating monomers with antibacterial and antifouling blocks were prepared by conjugating curcumin-derived curcumin carboxylic acid (Cur-COOH) with different chain lengths of allyl polyethylene glycol (APEG; MW 1200 or 2400). The coating monomer (APEG 1200/2400 -Cur) was grafted onto the surface of the titanium implant through azobisisobutyronitrile (ABIN)-induced radical polymerization to form dual-functional coatings with antibacterial and antifouling properties. Scanning electron microscopy & energy dispersive spectroscopy (SEM & EDS), contact angle (CA), and X-ray spectroscopy (XPS) confirmed successful grafting of coupling compounds. The coatings exhibited excellent antibacterial activity against Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus) and prevented biofilm formation. The coatings also reduced the adsorption of proteins and the adhesion of platelets, indicating their excellent antifouling properties. Notably, the coatings also exhibited favorable biocompatibility with mammalian erythrocytes and pre-osteoblasts. In summary, this dual-functional coating showed remarkable potential for application in preventing and treating infections caused by biofilms. [ABSTRACT FROM AUTHOR]

[Display omitted] • The MoNbTaWTi-based refractory high entropy alloy coatings by laser cladding. • TiN/(Nb, Ti) 5 Si 3 particles were in-situ synthesized by adding nano-Si 3 N 4. • The high-entropy alloy coating structure primarily consisted of BCC, TiN, and (Nb, Ti) 5 Si 3 phase. • The Si 3 N 4 -2.0 coating exhibits the best wear resistance with an average hardness of 628.07 HV 0.1. MoNbTaW Refractory High Entropy Alloy (RHEA) coating has caught the extensive interest of researchers due to its simple body-centered cubic structure and excellent room temperature plasticity. However, it is difficult to prepare refractory high-entropy alloy coatings by laser melting due to its high melting point. In this study, MoNbTaWTi (Si 3 N 4) x: (weight ratio; x = 0.5, 1.0, 1.5 and 2.0) RHEA composite coatings were fabricated by laser cladding on the Ti-6Al-4V alloy. The experimental results show that laser cladding may produce TiN/(Nb, Ti) 5 Si 3 ceramic particles and BCC phases in- situ in the coating when nano-Si 3 N 4 is added. Moreover, the in-situ reaction between element Ti and element N in the molten pool can be release a large amount of heat, which can efficiently facilitate the synthesis of RHEA coating. The in-situ generated TiN/(Nb, Ti) 5 Si 3 ceramic particles significantly increase the hardness and wear resistance of the composite coatings. The influence of the content of Si 3 N 4 on the ceramic morphology, microstructure, microhardness, and tribology of RHEA coatings was comprehensively evaluated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Well-structured RGO-LDH nanohybrid fillers are applied in the photothermal coating firstly. • The physical properties of the WPU nanocomposite coating increase visibly. • The coated fabric exhibits excellent anti-UV property and photothermal conversion performance. • Various durability tests demonstrates the remarkable photothermal stability properties of the coated fabric. The demand for photothermal fabrics requires more efficient photothermal nanoparticles and more stable interface binding fastness. Nanohybrid coating is considered as used as an efficient method to reach the goal. In this study, a nanohybrid of reduced graphene oxide-zinc-aluminum layered double metal hydroxide (RGO-LDH) was filled to WPU coating to prepare the photothermal textiles. RGO-LDH nanohybrid was surface modified by polydopamine (PDA) to improve the dispersion in WPU. In comparison to the pure WPU film, the WPU nanocomposite film exhibited enhanced water resistance, mechanical properties, and scratch resistance with the inclusion of nanohybrid filler at a 1 wt% concentration. Furthermore, the nanohybrid/WPU coated fabric showed excellent anti-ultraviolet (anti-UV) and photothermal conversion performance. The surface temperature of the nanohybrid/WPU coated fabric rose to 64 °C when exposed to a xenon lamp. After undergoing various durability tests including wearing, washing, folding, and bending, it was confirmed that the modified fabric had outstanding photothermal stability. This work provides a new strategy to fabricate the photothermal textile with excellent warming effect and weather resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Propose coating an assisted functional polythiourea on epoxy to significantly improve the flashover voltage in gases. • Establish the positive correlation between the flashover voltage and gas adsorption quantity. • Comprehensively clarify the effect of active function site characteristics on the gas adsorption quantity. • Reveal the underlying mechanism of the gas adsorption quantity on the flashover voltage. Surface flashover as a well-known discharge phenomenon on the gas–solid interface can lead to the failure of power equipment. Although intensive studies have been devoted to improving the flashover voltage in gases, the perspective on exploiting gas characteristics has so far been ignored. We here directly utilize a polythiourea-assisted coating on epoxy to achieve beneficial gas adsorption and enhance the flashover voltage. The results show that the flashover voltage of the polythiourea-assisted epoxy is significantly improved in both N 2 and SF 6 compared with the blank epoxy. Combining the experimental and computational results, it is proved that the striking improvement in the flashover performance is attributed to the increased gas adsorption quantity resulting from the unique thiourea units in polythiourea. Although both esters in epoxy and thioureas in polythiourea act as active function sites for guest gases, polar thioureas not only lead to pronounced charge displacements but also own the larger density, which further enhances the adsorption energy and promotes the gas adsorption. The resulting increased gas adsorption quantity prevents the collision ionization effectively, thus improving the flashover voltage. Our research innovatively proposes a functional polythiourea-assisted coating that can enhance the flashover voltage by improving the gas adsorption ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A slippery liquid-infused AgFP coating was fabricated via a simple electroless plating process followed by spontaneous polycondensation of PFOTES. • The AgFP coating demonstrated great stability and surface repellence against liquids with a wide range of surface tensions. • Fgn deposition on surfaces accelerated bacterial attachment and biofilm formation. • There exist two separate optimum regions of surface energies where bacterial adhesion and protein adsorption are minimal. • The AgFP coating exhibited enhanced anti-biofilm and anti-protein activities compared with traditional electroless coatings. In this work, a slippery liquid-infused silver-polytetrafluoroethylene (AgFP) coating was fabricated via a spontaneous polycondensation of 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES) onto an electroless AgF sublayer. The AgFP coating demonstrated great stability and superior repellence against liquids with a wide range of surface tensions. The anti-biofouling properties were investigated by adsorption of Escherichia coli , Staphylococcus aureus , fibrinogen, and bovine serum albumin. Owing to the self-cleaning property, the AgFP demonstrated enhanced anti-adhesion activity against both bacteria and proteins relative to traditional electroless coatings, despite the fibrinogen deposition significantly promoting bacterial binding. While its ultra-low surface energy was not within the optimum surface energy region for minimum bacterial or protein adhesion, the AgFP coating still displayed excellent anti-biofilm capability in a protein-bacteria co-deposition model, reducing over 80% of BSA-supplemented biomass coverage on Ag surfaces and over 60% of Fgn-supplemented biomass coverage on AgF surfaces, respectively. To understand the anti-adhesion mechanism, the XDLVO model was used to explain the adhesion behaviour of both bacteria and proteins. Cytotoxicity assays confirmed that the AgFP coating had good biocompatibility with fibroblast cells. The results from this research provide attractive prospects for the application of the AgFP coating in biomedical devices to combat infections. [ABSTRACT FROM AUTHOR]