Laser bioprinting is a promising method for biotechnology and medicine. This letter presents an experimental study of metal nanoparticles formed through the destruction of the absorbing Au or Ti ...films of the donor slide. It is shown that nanosecond laser action leads to the destruction of the film and the removal of its material with the formation of a hole with melted edges. A sharp increase in temperature above the melting point of the metal in the region of the hole leads to the destruction of the material with the formation of submicron nanoparticles. As a consequence, in the case of a gold film, nanoparticles formed due to material destruction are predominantly spherical. In using a titanium film, rectangular nanoparticles equal to the initial film thickness are formed.
ZnO microcrystal arrays have been grown on a (111) silicon substrate by the vapor‒liquid‒crystal deposition, where the liquid phase is gold. The differences between the crystals obtained for growth ...times of 5, 10, and 15 min are described. The lattice parameters of the microcrystals have been calculated with increasing growth time:
а
= 3.316 Å,
c
= 5.281 Å;
а
= 3.291 Å,
c
= 5.270 Å; and
а
= 3.286 Å,
c
= 5.258 Å. A change in the Au content in the microcrystals during their growth has been found to vary from 0.520 at % at the substrate to 0.035 at % on the surface of the crystals after the 15-min growth. Elemental distribution maps are presented, and the deviation of the lattice parameters of the obtained crystals from the reference values is explained.
The conductivity of Bi, Ga, In, and Sb nanocrystals deposited onto glassy carbon substrates by thermal evaporation at effect of laser irradiation at room temperature has been studied. The high ...surface conductivity of an array of spherical Bi, Ga, and In nanocrystals, in contrast to pyramidal Sb nanocrystals, has been found. Bi nanocrystals had the maximum conductivity at an average distance of
l
= 65 nm between them, which is smaller than the laser radiation wavelength by an order of magnitude. The results obtained confirm the hopping mechanism of surface conductivity of nanocrystals of Bi and Sb topological insulators, Ga and In metals.
In the following work by means of matrix synthesis the nanowire arrays of Fe–Ni alloy with elemental composition close to permalloy (Fe0·20Ni0.80) were obtained. In capacity of matrix the ...polyethylene terephthalate (PET) track membranes with angular distribution of pores within the range of ±30° and the diameter of pores in 100 nm were used. As a result, via electrochemical deposition method the metal-polymer composite in the form of nanowire arrays in the polymeric matrix were obtained. The distribution of pores over the surface of track membranes and the average amount of nanowire intersections under a variety of lengths of the grown nanowires were calculated. The resistivity of metal-polymer composite arrays, formed with nanowires of varying length, was measured. The growth boundary conditions and the lengths of nanowire arrays that are essential for obtaining of conducting metal-polymer composite were determined.
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•The PET track membrane (TM) used for the growth of nanowires was characterized.•A model for calculating the number of intersections of nanowires was proposed.•Resistance of an array of Fe0.2Ni0.8 nanowires was measured.•The correlation between the l and the Ncros. res. with 1/Raverage was established.
CdTe thin films were grown on Si(111) and Al
2
O
3
(0001) substrates by thermal vapor deposition. The obtained films were studied by atomic-force and scanning electron microscopy, as well as by X-ray ...diffraction analysis. It was found that thin films of both wurtzite and sphalerite CdTe modifications can be grown on Al
2
O
3
(0001) substrates. Thin films of the sphalerite CdTe modification can be obtained on Si substrates. It was shown that the elemental composition of thin films is close to stoichiometry, and, in the case of thin films grown on Al
2
O
3
(0001), the deviation was no more than 1 at %.
The effect of static and pulsed magnetic fields (~1 T) on the electrical conductivity of CdTe crystals has been revealed. With a delay after the magnetic exposure of crystals, the effect is observed ...in the form of two peaks of their conductivity with the subsequent relaxation return. The first peak at both types of magnetic treatment is observed ~1 h after exposure and its amplitude exceeds the background value by ~23–36% (the larger value corresponds to the static field). The second peak appears in both cases also at commensurate but much larger delays of ~50–60 h, and its amplitudes are much different for the two types of exposure, exceeding the background by ~60% for the static field and only by ~11% for the pulsed field. Possible mechanisms of the observed effects have been discussed.
Gallium nanostructures have been obtained on silicon substrates by thermal evaporation in an argon atmosphere. The sizes, density, and shape of Ga particles have been determined by computer ...processing of electron SEM-images. The condensation of Ga on Si substrates for 10, 15, and 20 s ensured the formation of the particles of several types: spherical, triangular, square, and in the form of rods and polyhedrons. The increase in the Ga condensation time to 20 s led to the increase in the density of spherical nanoparticles by 41%.
Preliminary comparative studies of the photoluminescent properties of two-dimensional ZnO nanostructures with morphology of nanowalls, nanosheets, and nanocombs, fabricated by gas-transport ...synthesis, have been performed. All structures exhibited near-band-edge (NBE) UV emission of the same order of intensity. Unlike nanocombs, whose spectrum contains a comparatively strong green luminescence band, nanowalls and nanosheets are characterized by a large ratio of the UV and visible components. This distinction is presumably due to the difference in the mechanisms of structure formation: nanowalls and nanosheets are formed according to the vapor–liquid–solid mechanism, whereas nanocombs grow according to the vapor–solid mechanism.
Polycrystalline Cd
Zn
х
Te (
x
= 0.005, 0.03, 0.05) ingots have been obtained by the modified Obreimov–Shubnikov method. The selected single-crystal blocks are studied applying the X-ray diffraction ...analysis, measurement of electrical characteristics, and magnetometry. The concentration dependence of changes in the magnetic and electrical properties of crystals is investiga11ted. It is established that at Zn concentrations of
x
= 0.03 and 0.05 ferromagnetic ordering is observed in clusters (inclusions) containing iron and/or nickel at 2 K, which is not observed for Cd
Zn
х
Te (
x
= 0.005) samples.
