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The aim of this work is to study the effect of irradiation with low-energy Kr14+ ions with an energy of 280 keV on radiation swelling and a decrease in the strength characteristics of high-entropy alloys based on the TiTaNbV system. The prospects of these studies are due to the possibility of obtaining new data on the radiation resistance of high-entropy alloys, which have great potential for use as structural materials for new-generation reactors. The choice of this type of irradiation and a dose of 5 × 1015 Kr/cm2 made it possible to simulate the effect of radiation swelling arising at a displacement per atom of 30–50 dpa in a small surface layer no more than 100–150 nm thick. During the studies carried out, it was found that the formed medium- and high-entropy alloys TaNbV and TiTaNbV have increased resistance to swelling and deformation of the crystal structure. At the same time, alloys of the NbV and TaNbV type have the highest degree of resistance to softening, while the TiTaNbV alloy has a lower resistance to swelling, since the addition of titanium leads to a decrease in the density and hardness of the alloy.

Using the electrochemical deposition method, Fe-doped CdSe films were obtained from electrolyte solutions. By varying an applied potential difference, films with different phase compositions were obtained: CdSe, FeSe/CdSe. At the same time, increasing the applied potential difference from 1.0 to 1.25–1.5 V leads not only to the formation of a new FeSe phase characteristic of a solid substitution solution, but also to a significant increase in the crystallinity degree and a decrease in dislocation density. According to elemental analysis, it was found that increasing the applied potential difference to 1.25–1.5 V leads to an increase in iron content in the structure by 4–5 times. Analysis of the morphological features of the synthesized films showed that the formation of the FeSe phase leads to an increase in grain sizes, as well as a roughness degree. According to the analysis of the optical characteristics of the synthesized films, the formation of the FeSe phase and the subsequent increase in its contribution leads to an increase in band gap from 1.69 to 1.93–1.98 eV, as well as a decrease in refractive index and reflection losses. The results obtained from evaluating the applicability of the synthesized films as a base for photocatalysts showed that films with double phases exhibit a high degree of photocatalytic degradation of an organic dye.

This article is devoted to the study of the efficiency of thermal annealing of nanostructures for phase transformations of the FeCo – Fe2CoO4/Co3O4-spinel type, as well as the subsequent application of the obtained nanotubes as a basis for anode materials of lithium-ion batteries. The choice of these types of nanotubes for use as a basis for anode materials is due to their structure, as well as the great potential of using spinel structures in this area, interest in which is manifested due to the possibility of accelerating lithiation processes and long-term preservation of the specific capacity of batteries. During the study, it was found that for spinel structures, the formation of oxide growths on the surface of nanotubes, the presence of which is associated with oxidative processes during annealing, is observed. Testing the applicability of these structures as anode materials showed that the formation of oxide spinel structures of type Fe2CoO4/Co3O4 leads to an increase in the number of cycles by 1.5–1.7 times compared to the original nanotubes. The efficiency of increasing the lifetime of anode materials is due to an increase in resistance to degradation of Fe2CoO4/Co3O4 structures, due to the formation of oxide phases, leading to an acceleration of lithation processes.

The aim of this work is to study the radiation damage processes, as well as their subsequent evolution and the effect on the structural, optical and mechanical properties of BeO ceramics. The choice of the type of Kr15+ ions with an energy of 140 meV makes it possible to simulate the kinetics of radiation damage comparable to the effect of uranium fission fragments in a nuclear reaction. Dose loads, which ranged from 1011 to 1015 ion/cm2, make it possible to simulate both single effects of radiation damage in the case of irradiation doses of 1011–1012 ion/cm2, and the effects of overlapping radiation damage and their mutual influence on changes in the properties of ceramics. During the studies carried out, the kinetics of changes in ceramics properties from the radiation dose was established, and the critical doses at which ceramics properties deteriorate sharply were determined. Studies showed that a growth in the radiation dose, leading to an increase in the defective areas overlap probability, leads to grain crushing and an increase in dislocation density, which in turn, leads to a slowdown in degradation processes of the ceramics strength and hardness.

This paper presents the results of studying the properties of TeO2-(1-x)ZnO-xSm2O3 glasses synthesized using the method of mechanochemical synthesis and subsequent thermal sintering. The control of the elemental composition was carried out using the method of energy dispersive analysis, the amorphous structure of the glasses was confirmed by the data of the results of measurements of X-ray diffraction. The shielding efficiency was evaluated by such parameters as Radiation protection efficiency, linear and mass attenuation coefficient and gamma radiation absorption, half-value layer and mean free path values. During the research, it was found that TeO2-0.2ZnO-0.8Sm2O3 glasses had the highest shielding efficiency. The results obtained can later be used for the design of protective materials and the development of technological processes for their production.

The paper presents the results of the study of structural, morphological, optical, and mechanical properties of lithium-containing ceramics obtained using the method of mechanochemical solid-phase synthesis. The purpose of this work is to assess the possibility of obtaining lithium-containing ceramics of the two-phase type, as well as the formation effect of the cubic phase of LiTiO2 on changes in the properties of ceramics. The relevance of this study is to obtain new data on the properties of lithium-containing ceramics, which have great prospects in their use as blanket materials for tritium reproduction. During the study, it was found that the formation of the LiTiO2 cubic phase leads to a change in the morphological features of ceramics, with the formation of sphere-like agglomerates of a nanoscale scale. An increase in the contribution of the LiTiO2 phase leads to a shift of the fundamental absorption edge, as well as the appearance of additional absorption bands. During mechanical tests for the determination of resistance to destruction by single compression, it was found that an increase in ceramic density, which is due to an increase in the contribution of the cubic phase, leads to an increase in resistance by 70–85%.

The work is devoted to the study of the effect of helium ion irradiation on the properties of ceramics based on Li2TiO3, which have great potential as a breeding blanket in the design of thermonuclear reactors. The choice of the type of ions and irradiation doses of 1–5 × 1017 ion/cm2 is due to the possibility of modeling the processes of defect formation as a result of the accumulation of helium in the structure of the surface layer of ceramics during their operation. As research methods, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used and the dielectric properties were studied by impedance spectroscopy. It was found that at irradiation doses of 1–3 × 1017 ion/cm2, these ceramics have high radiation resistance to structural changes, while increasing the radiation dose above 5 × 1017 ion/cm2 leads to significant changes in the properties of ceramics, which are caused by partial degradation of the surface layer of ceramics in the process exposure. As a result of measuring the strength characteristics, it was determined that the greatest decrease in the hardness of the surface layer occurs at an irradiation dose of 5 × 1017 ion/cm2. In the course of studying the dielectric characteristics, it was found that the main changes are associated with a decrease in the dielectric constant, as well as an insignificant shift of the maximum towards high temperatures, which is due to an increase in the concentration of defects in the structure of ceramics arising during irradiation.

The aim of this work is to assess the prospects of using CuBi2O4 composite films of various thicknesses as protective coatings against exposure to ionizing radiation of up to 150 MeV and doses of 1 × 1013–1015 ion/cm2, characteristic of the effects of overlapping cascade defects in the target. The relevance and novelty of the study lies in the search for alternative sources of screening for the effects of radiation damage to microelectronic devices without a significant increase in the mass–overall dimensions of microcircuits. This paper presents the results of a study of the radiation resistance of the structural, mechanical, and strength properties of synthesized CuBi2O4 films depending on the film thickness and radiation dose. Electrochemical deposition was used as a synthesis method, which allows one to control with high accuracy the phase composition and morphology of the synthesized films. Synthesized films were shown to possess a significant degree of stability to irradiation with the increasing film thickness from 5 to 10 μm. Moreover, in the case of films with a thickness of 3 μm, a decrease in the strength and structural properties is due to phase transition processes initiated by irradiation due to the transfer of energy to the crystalline subsystem as a result of elastic and inelastic collisions.

This work is dedicated to developing a simple methodology that allows for the application of a thermal annealing process, which can improve the conductivity of metallic nanostructures, embedded in porous track-etched membranes based on polyethylene terephthalate (PET TeMs), but at the same time, does not compromise the mechanical properties. Zinc, copper, and cobalt nanotubes (NTs) prepared by electrochemical deposition in PET TeMs were annealed at 200 °C for different time periods. The effects of annealing treatment on the structural and electrical properties were investigated by scanning electron microscopy, X-ray diffraction, and room-temperature resistance measurements. Choosing the appropriate annealing time for Zn or Cu-NTs allows controlling the formation of an oxide phase in these nanostructures. The presence of the oxide phase in an amount of no more than 10–15 wt% led to a decrease in the resistivity and an increase in the conductivity. Thermal annealing of Co-based NTs changed intensities of the metastable fcc β-Co and stable hcp α-Co phases. The metastable β-Co phase caused additional defects due to a change in the crystallite size after 90 min of thermal annealing.

The most important limitation for boron neutron capture therapy of cancer is the selective accumulation of boron compounds in tumor tissues in significant quantities. In this paper, we describe the possibility to use magnetic Ni/Fe nanotubes as carriers for boron delivery. Carborane derivatives containing 10 and 21 boron atoms per molecule were immobilized on Ni/Fe nanotubes by covalent and ionic interactions. Magnetic properties of NTs were investigated by Mossbauer spectroscopy. Structure, element, chemical composition, and morphology of obtained magnetic nanotubes were studied by XRD, SEM-EDA, and FTIR spectroscopy. Results indicate success immobilization of carborane derivatives on Ni/Fe nanotubes and great potential to use them as carriers for boron neutron cancer therapy of cancer.