Valeriy Borysenko

National Academy of Sciences of Ukraine | ISP · National Science Center Kharkov Institute of Physics and Technology

A comprehensive study of the technical parameters and conditions for the synthesis of ternary alloys in the Ti-Zr-Ni system by the "hydride cycle" method was carried out. The influence on the synthesis process of such parameters as: temperature and annealing time, heating rate, cooling conditions, material composition, dispersion, hydrogen content...

The synthesis of intermetallic material was carried out by means of dehydrogenating annealing of a (TiH 2) 30 Zr 45 Ni 25 sample in vacuum by an electron beam. The properties of the obtained material were studied for establishing the structural phase composition by scanning electron microscopy and X-ray structural analysis. It was found that prolon...

Aluminum-based quasicrystals form a wide class of icosahedral and decogonal systems, including Al-Fe-TM and Al-Cu-TM (TM are transition metals Ni, Co, Cr). Traditional methods for the synthesis of quasicrystalline materials, such as rapid quenching of liquid melts, the method of mechanical activation fusion, growing from the melt and others, have a...

The Ti30Zr45Ni25 intermetallic material was synthesized using the hydride cycle technology with dehydrogenation of a portion ofthe (TiH2)30Zr45Ni25 sample by an electron beam in vacuum. Using scanning electron microscopy (SEM / EDX) and X-raydiffraction (XRD) analysis, it was established that under the influence of an electron beam, structural tran...

In numerous papers [1,2], the possibility of synthesizing complex intermetallic and quasicrystalline materials based on refractory metals of the zirconium group using hydride technology has been shown. These materials are capable of reversibly absorbing hydrogen in significant quantities above 2 wt.% [3], which allows considering them as materials...

One of the new materials tested in our reactor was a melt spun Nd90Fe10 alloy with a large degree of amorphous or quasicrystalline phase. A fierce exothermic reaction was detected in Nd90Fe10 films upon filling them with hydrogen or deuterium and heating up to ~300 C, which resulted in the melting of the samples and the Cu foil, in which the sample...

A fierce exothermic reaction was detected in Nd90Fe10 films with sufficient degree of amorphous phase upon filling them with hydrogen or deuterium, which resulted in the melting of the samples and the Cu foil, in which the samples have been wrapped. Quantitative analysis have shown that the amount of heat produced in large Nd90Fe10 samples in our e...

We show that it is reasonable to develop one of the types of new high-performance radiation-protective materials, namely, “light metal + heavy metal” multilayer composites. The characteristics of the internal architecture of Al–Pb composites prepared by the successive application of vacuum and normal atmospheric rolling are presented. The differenc...

We summarize an extensive study on the impact of absorber layer defect density on the performance of amorphous (a-Si:H) and microcrystalline (μc-Si:H) silicon solar cells. To study the effects of the absorber layer defect density we subjected set of a-Si:H and μc-Si:H cells to a 2 MeV electron bombardment. Subsequently the cells were stepwise annea...

Theoretically predicted values of the open circuit voltage (VOC) for a-Si:H or μc-Si:H based solar cells are substantially higher than the values achieved in of state-of-the-art devices. Fundamentally, open circuit voltage is determined by generation-recombination kinetics, where recombination is often controlled by the defect density in the absorb...

We describe the methods and the results of the experiments with passing of monochromatic beams of electrons with an energy of 2.5 МеV through specimens of aluminum and Al–Pb layered composites with different internal architectures. It is shown that, as compared with aluminum, the investigated composites are characterized by a higher absorptivity. T...

The impact of defects on the performance of p- and n-side illuminated microcrystalline silicon solar cells is investigated. The absorber layer spin density NS is controlled over some two orders of magnitude by electron bombardment and subsequent annealing steps. At increased NS (between 3 × 1016 and 1018 cm−3), performance of n-side illuminated cel...

Improvement of the performance of solar cells based on amorphous (a-Si:H) and microcrystalline (μc-Si:H) silicon requires understanding of the role of the deep defects – dangling bonds – in the bulk of the intrinsic a-Si:H or μc-Si:H absorber layers. A straightforward way to understand how these defects may affect the performance of the cells is to...

After irradiation of hydrogenated amorphous and microcrystalline silicon (a-Si:H and μc-Si:H) with 2 MeV electrons at 100 K, we observe satellite-like components close to the dominating electron spin resonance (ESR) signal of these materials. The satellites overlap with the commonly observed dangling bond resonance and are proposed to originate fro...

The effect of the defect density in hydrogenated amorphous and microcrystalline silicon (a-Si:H and µc-Si:H) absorber layers on the performance of thin film solar cells was investigated. The defect density was varied reproducibly over more than two orders of magnitude by 2 MeV electron bombardment and subsequent thermal annealing. Considerable quan...

The effect of the defect density in hydrogenated amorphous and microcrystalline silicon (a-Si:H and μc-Si:H) absorber layers on the performance of thin film solar cells was investigated. The defect density was varied reproducibly over more than two orders of magnitude by 2 MeV electron bombardment and subsequent thermal annealing. Considerable quan...

The 2.5 MeV electron-irradiation and resistance-recovery experiments were performed. It was found that the majority of atoms of a (Zr0.55Al0.10Ni0.05Cu0.30)99Y1 bulk metallic glass (BMG) possess a locally preferred order, and vacancies are stable point defects. Low- and high-frequency compression–compression fatigue experiments show that the fatigu...

The raw single wall carbon nanotubes (SWCNT) were chemically and thermally treated and then milled in ball mill. After this SWCNT were irradiated by electron beam with energy 2.3 MeV up to fluence 1014 e-/cm2 at room temperature. Then SWCNT were saturated with hydrogen at pressure 5 bar and quenching down to the temperature 78 K. The sorption capab...

Pinning force Fp variation with the magnetic field H and the angle α = ∠H, ab is investigated in crystals having different concentrations of point defects npd. Comparison between the functions Fp (H) and Fp (α) strongly suggests that the minimum position in the Fp (α) -curve corresponds to the angle αOD, which separates the ordered vortex lattice (...

ESR and conductivity studies have been preformed on μc-Si:H exposed to 2 MeV electron bombardment and successive annealing in order to investigate the influence of the defect density on the electronic properties of n-type μc-Si:H. With this approach one can vary the defect density in one and the same sample and directly deduce its influence on the...

The recovery processes at the isothermal annealing of point defects in zirconium low-doped alloys Zr-Sc, Zr-Dy, Zr-Y, Zr-Gd, Zr-La have been investigated after the low-temperature electron irradiation by 2 MeV. It has been found that the migration energy of interstitial atoms in zirconium is equal to 0.34 eV as well as the migration energy of vacan...

Studies were made into the influence of oversized rare-earth atoms on the processes of radiation defect accumulation and annealing in two-component zirconium alloys. Zr and Zr-X alloys (where X = Sc, Dy, Y, Gd and La) have been irradiated with 2 MeV electrons at 82 K. The radiation-induced resistivity has been measured in situ as a function of dose...

The sensitivity of radiation effects on structural features in metallic glasses (MG) provides a way of investigating the structure and structural defects of MG through the studies of accumulation and relaxation processes of radiation damages in the glasses. In particular, it is a way to verify the validity of models proposed for the MG structure. C...

The influence of dangling-bond defects and the position of the Fermi level on the charge carrier transport properties in undoped and phosphorous doped thin-film silicon with structure compositions all the way from highly crystalline to amorphous is investigated. The dangling-bond density is varied reproducibly over several orders of magnitude by el...

The report deals with damage kinetics, defect evolution and radiation response of binary and multicomponent solids irradiated with MeV electrons. Studies were made into such systems as metallic alloys, semiconductors, high-T{sub c} superconductors and bulk metallic glasses. The common features of the studies involve the efficient use of MeV dc elec...

The influence of the oversized atoms of rare-earth metals (Sc, Dy, Y, Gd, and La) on the kinetics of accumulation and annealing of radiation defects in zirconium irradiated by electrons with the energy 2 MeV, at a temperature of 82 K is represented. An existence of the regions of tension and compression around the oversized impurity atoms is experi...

Defect creation by MeV electron bombardment of a-Si:H and μc-Si:H thin films is used to explore hidden features of the electron spin resonance spectra. Different dynamics of creation and annealing for different paramagnetic states is expected and found. In a-Si:H the g-value of the db resonance does not change after irradiation, but a pair of satel...

Accumulation and recovery kinetics of radiation damages in Zr 46.8Ti 8.2Cu 7.5Ni 10Be 27.5 and Zr 52.5Ti 5Cu 17.9Ni 14.6Al 10 metallic glasses was investigated by means of low temperature electron irradiation and electrical resistance measurements. The linear dose dependence of resistance is a manifestation of accumulation of irradiation defects wi...

The processes of point defects annealing in low-alloyed materials Zr-Sc and Zr-Y, after low-temperature irradiation with 2 MeV electrons has been investigated. The temperature intervals of main stages of irradiation are determined. The splitting of the peak of annealing Stage III in Zr-Y alloys has been detected.

Paramagnetic defects in amorphous and microcrystalline silicon (a-Si:H and μc-Si:H) with various structure compositions and doping levels were investigated by electron spin resonance (ESR). Samples were prepared by PECVD. The defect density was varied with 2 MeV electron bombardment at 100 K and stepwise annealing in the range of 80 K–433 K. In int...

Defects in thin film silicon with different structure all the way from amorphous to microcrystalline were investigated by electron spin resonance with emphasis on amorphous material prepared close to the transition to crystalline growth. Electron beam irradiation and stepwise annealing is used for reversible variation of the defect density over thr...

The defect density in thin film silicon was increased using low temperature 2MeV electron irradiation up to a factor of 1000. More than 30 samples of different structure from highly crystalline to amorphous were prepared with PECVD and irradiated to study the dynamics of defect accumulation and role of the material structure in this process.

Amorphous and microcrystalline silicon are well known materials for thin film large area electronics. The defects in the material are an important issue for the device quality and the manufacturing process optimization. We study defects in thin film silicon with electron spin resonance (ESR). In order to vary the defect density in a wide range 2 Me...

The photoexcitation of Sr-87m (energy of isomeric level E-iso = 388.532 keV) using the gamma rays produced by electron electrostatic accelerator was examined for the bremsstrahlung end-points energy covered the range from 1.4 to 3.1 MeV. Isomer activation yield was measured and intermediate states (IS) 1228, 1770, 1920 and 2656 keV contribution wer...

Paramagnetic defects in μc-Si:H and a-Si:H with various structure compositions were investigated by electron spin resonance (ESR). The defect density was varied by high energy electron bombardment and subsequent annealing. The spin density increases by up to 3 orders of magnitude. In most cases the initial spin density can be restored upon annealin...

Results of examination of spectrometer performances CdTe (CdZnTe) detectors are submitted at recording gamma radiations in a range of 15 - 500 keV, and alpha radiations in a range of 4 - 8 MeV. It was shown, that such detectors may be used for the solution of analytical problems with definition of elements from lanthanum up to plutonium with record...