Studying the properties of Fe and Fe–Co nanotubes in polymer ion-track membranes

Iron and iron–cobalt nanostructures are probed by means of Mössbauer spectroscopy combined with scanning electron microscopy, energy-dispersion analysis, and X-ray diffraction. The obtained nanostructures are single-phase Fe_{1 ? x}Co _x (0 ≤ x ≤ 1) nanotubes that have high degrees of polycrystallinity and a bcc lattice 12 μm long and 110 ± 3 nm in diameter, with walls 21 ± 2 nm thick. A random distribution of the orientations of the magnetic momenta of Fe atoms are observed for Fe nanotubes, while Fe–Co nanotubes are characterized by a magnetic texture along their axes.     

Structural features of Ag-Cu alloy films produced by the codeposition of sputtered metals

Solid solutions in the form of alloy coatings are obtained in the entire concentration range of binary system using ion-plasma sputtering and the codeposition of Ag and Cu ultrafine particles. Sstudying the structure of solid solutions shows a change in the FCC-lattice parameters from silver to copper with a characteristic bend corresponding to the eutectic composition of the equilibrium phase diagram. Solid-solution decay begins at 100°C, and their complete decomposition occurs at 250°C. The surface structure of the initial solutions is presented by crystallites 20–30 nm in cross section; after decomposition, their size is less than 100 nm. For the latter, the distortions of the lattice parameters are 0.32% for a solution of Cu in Ag and 0.29% for a solution of Ag in Cu. The method of alloy production can be extended to the systems of metals immiscible in the solid phase.     

Synthesis and properties of Fe/Ni nanotubes

Fe/Ni nanotubes were formed in pores of polyethylenterephtalate-based template matrices by electrochemical deposition. The inner diameter, wall height, and thickness of the nanostructures, as well as the elemental and phase compositions, can be controlled by varying the deposition conditions. The volume deposition rate constants have been determined for each potential difference, due to which the nanostructure growth could be controlled. An X-ray diffraction analysis of the samples obtained at a potential difference of 1-1.6 V has revealed their composition to correspond to the substitutional solid solution, with an iron atom replaced by a nickel atom and dominance of the bcc a-Fe phase. The samples obtained at a potential difference of 1.8–2 V contain the bcc a-Fe phase and fcc Ni phase; the fcc phase dominates in the sample obtained at a potential difference of 2 V, which can be related to the high Ni content in nanotubes.     

Study of the use of ionizing radiation for the modification of CoO/Co0.65Zn0.35 nanostructures

The paper presents the results of a study of the influence of heavy ions Xe²²⁺ on the morphology, phase composition, structural and conductive characteristics of CoO/Co_0.65Zn_0.35 nanowires obtained by the method of electrochemical synthesis. As a result of the research, it was established that an increase in the irradiation fluence leads to a change in the phase composition, due to the decomposition of the oxide phase CoO and the predominance of Co_0.65Zn_0.35 substitution in the structure of the cubic phase of solid solution. It has been established that an increase in the irradiation fluence and a decrease in the oxide phase in the structure leads to a decrease in the concentration of dislocations and vacancies in the nanowires, which indicates a partial relaxation of defects as a result of irradiation. It is established that a change in dislocation and vacancy density leads to an increase in the value of specific conductivity and a decrease in resistance.     

Production of Intense Ion Beams of Boron and Iron Using the MIVOC Method from ECR Ion Source on the DC-60 Cyclotron

This article describes experiments carried out in 2017–2018 at the DC-60 accelerator complex (Astana branch of the Institute of Nuclear Physics, Almaty, Kazakhstan) to develop methods for producing intense beams of multicharged iron and boron ions with the use of volatile organometallic compounds (Metal Ions from Volatile Compounds (MIVOC)). Beams of iron and boron ions were obtained for the first time on the DC-60 cyclotron, and the acceleration modes of ⁵⁶Fe¹⁰⁺ and 11B²⁺ ions were optimized to energies of 1.75 and 1.5 MeV/n, respectively.     

Structure and physical properties of iron nanotubes obtained by template synthesis

Physics of the Solid State - Iron nanotubes with an aspect ratio of approximately 100 are synthesized by electrochemical deposition using polyethylene terephthalate templates. The structural and...     

A Mössbauer study of iron and iron–cobalt nanotubes in polymer ion-track membranes

Iron and iron–cobalt nanostructures that were synthesized in polymer ion-track membranes have been studied via Mössbauer spectroscopy combined with raster electron microscopy, energy-dispersion analysis, and X-ray diffraction data. The obtained nanostructures are single-phase bcc Fe_1–xCo_x nanotubes with a high degree of polycrystallinity, whose length is 12 μm; their diameter is 110 ± 3 nm and the wall thickness is 21 ± 2 nm. Fe²⁺ and Fe³⁺ cations were detected in the nanotubes, which belong to iron salts that were used and formed in the electrochemical deposition. The Fe nanotubes exhibit eventual magnetic moment direction distributions of Fe atoms, whereas Fe/Co nanotubes have a partial magnetic structure along the nanotube axis with a mean value of the angle between the magnetic moment and nanotube axis of 34° ± 2°. Substituting the Fe atom with Co in the nearest environment of the Fe atom within the Fe/Co structure of nanotubes leads to a noticeable increase in the hyperfine magnetic field at the ⁵⁷Fe nuclei (by 8.7 ± 0.4 kOe) and to a slight decrease in the shift of the Mössbauer line (by 0.005 ± 0.004 mm/s).