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Epoxy-acrylate (EA) core–shell nanoparticles have gained significant attention recently due to their dual unique properties as heterogeneous materials, particularly in coating applications. However, the effect of epoxy (EP) concentration in core layer on mechanical properties is still limited, and the mechanism of how it affects the film's performance is not well understood. In this study, we investigate the effect of varying EP concentration in the core layer on the mechanical properties of nanostructured films containing EA core–shell nanoparticles. The core–shell nanoparticles were synthesized through multistage seeded emulsion polymerization. The transmission electron microscopy (TEM) images revealed similar particle morphology and size in all EA nanoparticles. Differential scanning calorimetry (DSC) analysis confirmed the successful synthesis of core–shell particle morphology with two glass transition temperature (Tg) values (~12 °C and ~ 60 °C) observed for the core and shell layers, respectively. We observed an increase in the Tg values of the shell layer with higher EP content in the core layer. The use of EP-based copolymers raised the Tg values of the shell layer, significantly affecting the film formation behavior and their mechanical properties through interlayer crosslinking. Tensile modulus values for the films ranged from 200 to 500 MPa, marking the highest modulus reported for cast films of EA nanostructured films. Our findings reveal a straightforward and versatile method for producing high-modulus EA nanostructured films with customizable mechanical properties, making the model ideal for enhancing wood coating performance. [ABSTRACT FROM AUTHOR]

Copper-doped cadmium sulfide (CdS:Cu) nanocrystalline thin films were coated on glass substrates with different Cu concentrations (0 wt.%, 3 wt.%, and 6 wt.%) using the sol–gel spin coating technique. X-ray diffraction (XRD) spectrometry, scanning electron microscope (SEM), and energy-dispersive X-ray (EDX) analysis were used to analyze the average crystallite size, surface morphology, and chemical analysis of prepared thin films in 3 and 6 wt.% of Cu concentrations. According to the XRD results and SEM micrographs, nanocrystalline grains of doped thin films have an almost regular geometric shape, which become slightly larger by increasing Cu concentration from 3 to 6 wt.%. The optical and electrical characteristics of all three films were examined by spectroscopy ellipsometry (SE) technique in the wavelength range between 300 and 900 nm. Based on the SE results, the thin film prepared with 0 wt.% Cu concentration showed a higher refractive index, extinction coefficient, and absorbance compared to the other Cu-doped thin films. The CdS:Cu thin films with 3 and 6 wt.% Cu concentrations demonstrated significantly higher transparency than pure ones (0 wt.% Cu doped), making them particularly suitable for different optoelectronic applications. Moreover, the optical band gap energy (Eg) values were evaluated. It can be concluded that the pure film has the largest band gap energy, and Cu doping reduces the Eg values. The spin-coated 6 wt.% CdS:Cu thin film showed high transparency (67.83%), good homogeneity, and a substantial Eg value (2.6 eV), making it ideal for photocatalytic and photovoltaic applications. [ABSTRACT FROM AUTHOR]

A nanostructured gas sensors made of the Fe2O3:ZnO (60 : 40 wt %) composition were fabricated. The SEM image of the gas sensitive film showed that the particle sizes in the film are ranged from 20–50 nm. The gas sensitivity characteristics of the Fe2O3:ZnO sensor to hydrogen were studied at various operating temperatures (50–250°C) and in the presence of various hydrogen concentrations (75–2000 ppm) in the ambient air. The investigated Fe2O3:ZnO sensor showed sensitivity to hydrogen starting from a temperature of 50°C, and the maximum response was observed at an operating temperature of 100°C, at which the response exceeded 5000. The optimal combination of sensor gas sensitivity parameters was observed at an operating temperature of 200°C. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the yttrium concentration on the structure of coatings prepared via the high-frequency magnetron sputtering of a metal target is investigated. The results of coating deposition in pure argon and a mixed (Ar + O2), reactive medium are discussed. It is demonstrated that a nonequilibrium body-centered-cubic solid solution based on zirconium with an extended homogeneous region (up to 16 at % Y) is formed under the condition that a target is sputtered in pure argon. During reactive-coating deposition, the formation of cubic or tetragonal zirconium dioxide is generated depending on the yttrium concentration. The tetragonal structure is created if the yttrium concentration is 8 at %. It is found that the obtained tetragonal zirconium dioxide is thermally stable both in terms of structure and in morphology upon heat treatment in air at 1100°C for 11 h. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to examine the extent of thermal injury in the brain after the use of a minimally invasive electrosurgical device with a nanostructured copper-doped diamond-like carbon (DLC-Cu) surface coating. To effectively utilize an electrosurgical device in clinical surgery, it is important to decrease the thermal injury to the adjacent tissues. The surface characteristics and morphology of DLC-Cu thin film was evaluated using a contact angle goniometer, scanning electron microscopy, and atomic force microscopy. Three-dimensional biomedical brain models were reconstructed using magnetic resonance images to simulate the electrosurgical procedure. Results indicated that the temperature was reduced significantly when a minimally invasive electrosurgical device with a DLC-Cu thin film coating (DLC-Cu-SS) was used. Temperatures decreased with the use of devices with increasing film thickness. Thermographic data revealed that surgical temperatures in an animal model were significantly lower with the DLC-Cu-SS electrosurgical device compared to an untreated device. Furthermore, the DLC-Cu-SS device created a relatively small region of injury and lateral thermal range. As described above, the biomedical nanostructured film reduced excessive thermal injury with the use of a minimally invasive electrosurgical device in the brain. [ABSTRACT FROM AUTHOR]

The electrostatic layer-by-layer technique has been exploited as an useful strategy for fabrication of nanostructured thin films, in which specific properties can be controlled at the molecular level. Ferrofluids consist of a colloidal suspension of magnetic grains (with only a few nanometers of diameter) with present interesting physical properties and applications, ranging from telecommunication to drug delivery systems. In this article, we developed a new strategy to manipulate ferrofluids upon their immobilization in nanostructured layered films in conjunction with conventional polyelectrolytes using the layer-by-layer technique. We investigated the morphological, optical, and magnetic properties of the immobilized ferrofluid as a function of number of bilayers presented in the films. Ferrofluid/polyelectrolyte multilayers homogeneously covered the substrates surface, and the magnetic and optical properties of films exhibited a linear dependence on the number of bilayers adsorbed. [ABSTRACT FROM AUTHOR]

Nanostructured titanium oxide films were fabricated by vacuum-plasma spraying. The microstructure of the films was characterized with SEM, TEM, and XRD. The chemical state of the titanium oxide of the films was analyzed using XPS. The results indicated that the vacuum-plasma sprayed nanostructured titanium oxide films possessed a corallike structure with small pores and agglomerated grains, which was composed of nanosized particles. The main phases of the films were anatase and rutile, and their relative content was determined by the plasma parameters. Low-valence titanium cations were also found in the films. [ABSTRACT FROM AUTHOR]