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This study aims to improve the photocatalytic properties of titanium dioxide nanorods (TNRs) and other related nanostructures (dense nanorods, needle-like nanorods, nanoballs, and nanoflowers) by modifying them with silver nanoparticles (AgNPs). This preparation is carried out using a two-step method: sol–gel dip-coating deposition combined with hydrothermal crystal growth. Further modification with AgNPs was achieved through the photoreduction of Ag+ ions under UV illumination. The investigation explores the impact of different growth factors on the morphological development of TiO2 nanostructures by modulating (i) the chemical composition, the water:acid ratio, (ii) the precursor concentration involved in the hydrothermal process, and (iii) the duration of the hydrothermal reaction. Morphological characteristics, including the length, diameter, and nanorod density of the nanostructures, were analyzed using scanning electron microscope (SEM). The chemical states were determined through use of the X-ray photoelectron spectroscopy (XPS) technique, while phase composition and crystalline structure analysis was performed using the Grazing Incidence X-ray Diffraction (GIXRD) method. The results indicate that various nanostructures (dense nanorods, needle-like nanorods, nanoballs, and nanoflowers) can be obtained by modifying these parameters. The photocatalytic efficiency of these nanostructures and Ag-coated nanostructures was assessed by measuring the degradation of the organic dye rhodamine B (RhB) under both ultraviolet (UV) irradiation and visible light. The results clearly show that UV light causes the RhB solution to lose its color, whereas under visible light RhB changes into rhodamine 110, indicating a successful photocatalytic transformation. The nanoball-like structures' modification with the active metal silver (TNRs 4 Ag) exhibited high photocatalytic efficiency under both ultraviolet (UV) and visible light for different chemical composition parameters. The nanorod structure (TNRs 2 Ag) is more efficient under UV, but under visible-light photocatalyst, the TNRs 6 Ag (dense nanorods) sample is more effective. [ABSTRACT FROM AUTHOR]

Continuous hard protective layers on soft substrates working under elastic deformation conditions are prone to uncontrolled cracking and detaching from the substrate during bending and straining. Implementation of a noncontinuous hard pattern deposited on the surface allows such an antiwear layer to freely deform with the substrate. The idea was demonstrated for patterns made of regularly spaced, micrometer range sized nanocomposite islands. The nanocomposite used consisted of an epoxy resin matrix and superhard silicon carbide nanoparticles as a reinforcing component. Good dispersion of nanoparticles in the matrix was verified by means of atomic force microscopy. The significant improvement in wear resistance was measured under an applied load in the millinewton range using a custom-made microtribometer, and in the newton range using ball-on-disk apparatus. Such a system can be applied in textile machines and elastic yarn tensioners for damping the longitudinal component of vibrations, largely influencing the quality of the fabric obtained. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a detailed magnetic force microscopy study has been made of the domain structure of isotropic nanocomposite Nd2Fe14B/Fe3B magnet ribbons prepared by melt-spinning. The domain structure is composed of interaction domains a few hundred nanometers in size, which indicates the presence of a strong exchange coupling between the grains. Within the interaction domains, a fine substructure on the same scale as the grain size is observed with high-contrast and clarity, which is an improvement over earlier results. As a consequence, the interaction domains are clusters of many single-domain grains whose magnetization directions are not precisely the same but differ slightly. In general, the interaction domains have both perpendicular and in-plane magnetization components. The domain width of the interaction domains (260±20)nm was determined by digital means (using the method of Bodenberger and Hubert), in contrast to previous investigations. [Copyright &y& Elsevier]