Oleksandr Kolomys

Oleksandr Kolomys
National Academy of Sciences of Ukraine | ISP · V. E. Lashkaryov Institute of Semiconductor Physics

PhD

About

108
Publications
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611
Citations
Citations since 2016
46 Research Items
445 Citations
2016201720182019202020212022020406080
2016201720182019202020212022020406080
2016201720182019202020212022020406080
2016201720182019202020212022020406080

Publications

Publications (108)
Presentation
Full-text available
The results of this study indicate that titanium dioxide nanoparticles (nano-TiO2) possess adsorptive, photocatalytic, bactericidal, virucidal and fungicidal properties, which are used in antibacterial coating, for air and water disinfection. In parallel with studies of the physicochemical characteristics of titanium dioxide, its toxicological asse...
Article
Full-text available
Nanosized composites CeO2–Ag, La2O3–Ag, and TiO2–Ag are a class of nanomaterials suitable for photocatalysis, optical devices, and photoelectrochemical elements. Further, nanocomposites with several wt.% of silver can be used as creating materials for pathogenic virus inactivation with pandemic-neutralizing potential. Thus, CeO2–Ag, La2O3–Ag, and T...
Article
Full-text available
Citation: Lavrynenko, O.M.; Zahornyi, M.M.; Vember, V.V.; Pavlenko, O.Y.; Lobunets, T.F.; Kolomys, O.F.; Povnitsa, O.Y.; Artiukh, L.O.; Naumenko, K.S.; Zahorodnia, S.D.; et al. Nanocomposites Based on Cerium, Lanthanum, and Titanium Oxides Doped with Silver for Biomedical Application. Condens. Matter 2022, 7, 45. https://doi.org/10.3390/ condmat703...
Article
Full-text available
Cu–Al–O thin films were grown on Si (111) substrates by using the reactive ion-beam sputtering (RIBS) method within the temperature range 80 to 380 °C. The effect of thermal annealing of Cu–Al–O films under various regimes of cooling on the microstructure, morphology, optical properties and photocatalytic activity were examined. The properties of a...
Article
Full-text available
А series of Ag/TiO2 is prepared by the chemical deposition method using silver nitrate and suspension of TiO(OH)2. Silver nanoparticles are deposited on the surface and inside TiO2 nanoparticles depending on the Ag concentration. The Ag/TiO2 composites are characterized by x-ray diffraction, transmission electron microscopy, scanning electron micro...
Article
Full-text available
The ZnO and TiO2 nanopowders have been prepared by means of the pulsed laser reactive ablation of metallic (Zn, Ti) targets. The Structural, optical, and luminescent studies have been done using by X-ray diffractometry, electron microscopy, transmission, Raman and photoluminescent spectroscopy. All nanopowders having high optical transmission in th...
Article
In this paper we investigate the doping effect of FeO and Fe2 O3 on the structural, optical and magnetic properties of ZnO layers prepared by a new stencil-free technique. Samples were characterized by X-ray diffraction (XRD), atom force and magnetic force microscopy, photoluminescence and Raman spectroscopy. A quite high quality of the printed Fe-...
Article
Full-text available
Ag/TiO2 nanoparticles (NPs) were prepared by a simple chemical deposition method using silver nitrate and suspension of TiO(OH)2. Silver NPs were deposited on the surface and inside of TiO2 NPs depended on the Ag concentration. The Ag/TiO2 composites were characterized by X-ray diffraction, transmission electron microscopy, scanning electron micros...
Article
The results of studies of printed ZnO:Co polycrystalline layers are first described. The layers with Co concentration of 0.78, 2.09 and 5.42 at.% were printed by a new stencil-free method developed by the authors and then were recrystallized at a temperature 1000–1100 °C. It was shown that the layers were polycrystalline with a typical grain size a...
Article
For the synthesis of nanostructured ZnO, the electrolytic method developed by the authors was used, the advantages of which are the environmentally friendly and low-cost process, low synthesis temperatures (20-98°C), and no need for complex equipment. The developed method allows to obtain low-dispersion materials of different elemental composition,...
Article
Full-text available
The properties of nanosized ZnO:Ho thin films deposited by the explosive evaporation method have been studied. This work is aimed at studying the effect of high deposition rate on the oxide characteristics interesting from the viewpoint of photocatalysis, namely: morphology and structure, electrical and optical properties, a lifetime of charge carr...
Article
Studies of magnetization of undoped and Mn-doped nanosized titanium dioxide powders showed that its dependence on the magnetic field can be approximated by the function that is a linear combination of two Langevin functions with different parameters. The linear part along with the diamagnetic contribution typical for metal oxides is due to the cont...
Chapter
Full-text available
The change in the degree of crystallinity and dynamic elastic, shear modulus in pure polyvinyl chloride (PVC) and its composites with methylene blue dye (MB) up to 0.07 vol. fract. were investigated with X-ray diffraction and the spread of high-frequency ultrasound methods. The characteristics change difficultly as the content of MB increases. The...
Article
Manganese spatial distribution in ZnO:Mn ceramics (0.1–5 at.% Mn) sintered at 1100 °C in air has been investigated using Electron paramagnetic resonance (EPR), micro-Raman and Diffuse reflectance spectroscopy. The Raman and EPR spectra show that concentration of Mn incorporated in ZnO grains decreases from the surface of ceramic sample to its depth...
Article
The effects of built-in deformation and stress relaxation on the structural and optical properties for a 21-period AlN/GaN superlattice (SL) after implantation with argon ions have been studied. Upon implantation, the satellites’ peaks in the X-ray diffraction spectra shift toward the smaller angles which indicate decreasing of tensile deformation...
Article
Full-text available
The methods of optical absorption spectroscopy and high-resolution diffractometry have been used to study the influence of microwaves oncharacteristics of crystalline SiC. Being based on the X-ray analysis data, optical transmission, photoluminescence, and photoluminescence excitation spectra, it has been shown that the microwave treatmentleads to...
Article
Optical properties of as‐grown high nitrogen‐doped ZnO:Al,N films (with a variation of nitrogen concentration from 2.3 to 4.3 atomic %) were studied by Raman, photoluminescence and FTIR spectroscopy. The Al (LO) mode peaked at 580 cm⁻¹ is increased with increasing nitrogen concentration. The silent mode B1low at 275 cm⁻¹ is clearly observed testify...
Article
Full-text available
The dependence of the charge carrier’s release from traps on the polymer ordering and the widths of the vibration bands are investigated in five silicon organic polymers using thermoluminescence in the 5–200 K temperature range and the Raman spectra. The influence of the vibrations on the thermoluminescence is caused by the processes of the charge...
Article
The influence of rapid thermal annealing (RTA) on structural and optical properties of ZnO multilayer structures co-doped with Tb and Eu ions has been investigated by X-ray diffraction, Time-of-Fligth Secondary Ion Mass Spectrometry, Specular Infrared reflection, micro-Raman and photoluminescence (PL) methods. It is shown that incorporation of rare...
Conference Paper
Full-text available
Surface-enhanced Raman scattering (SERS) is powerful analytical method for applications in fundamental and applied research. One of the most active field in SERS research relates to the quest for new substrates with improved enhancement efficiency and reproducibility. These efforts include several approaches, such as development of new nanomaterial...
Article
Full-text available
The morphology and microstructure of the Pb1−xSnxTe surfaces polished by the H2O2–HBr–ethylene glycol etchants have been investigated using atomic force and electron microscopy techniques. Treatment of the Pb0.8Sn0.2Te crystal surfaces with new etchant mixtures allows to obtain ultra-smooth surfaces Ra < 1 nm. The single crystal surfaces after chem...
Article
The effect of substrate material (Si, SiO2,Al2O3) on structural, optical and electrical properties of terbium doped ZnO films (Tb-ZnO) has been investigated by the X-ray diffraction, Raman scattering, atomic force microscopy, photoluminescence and infrared reflection methods. All films consist of micron size clusters of closely packed ZnO grains separat...
Article
Study of AlN simultaneous doping and thermal annealing influence on the properties of ZnO films is very important for achievement as p-type conductivity in the films as for improvement the performance of ZnO-based ultraviolet detectors. Highly-doped ZnO: Al, N films containing the Zn3N2 phase (ZnO: Al, N-Zn3N2) were grown on Si substrates by magnet...
Article
The structural phase transitions in the intercalate layer in bromine intercalated compounds based on fine crystalline anisotropic graphite are investigated by the Raman spectroscopy method. The changes of Raman spectra with the temperature for a graphite intercalation compound with bromine are considered. The temperature dependences of parameters o...
Article
The features of the InAs, InSb, GaAs, and GaSb ultra-smooth surface have been investigated using chemical–mechanical polishing with the (NH4)2Cr2O7–HBr–CH2(OH)CH2(OH)-etching solutions. The etching rate of the semiconductors has been measured as a function of the solution saturation by organic solvent (ethylene glycol). It was found that mechanical...
Article
High-quality thin ZnO layers are fabricated by means sol-gel technology, they being used to form transparent electrodes in up-to-date optoelectronic devices of various applications. The ranges of parameters of technological process have been found which allow growing zinc oxide layers on crystal silicon and glass substrates. The technological condi...
Article
The morphology and microstructure of PbTe surfaces polished with H2O2-HBr-ethylene glycol solutions have been studied by atomic force and electron microscopy techniques. The surface of PbTe single crystals after chemical-mechanical and dynamic chemical polishing with bromine-releasing etchants has been examined by optical microscopy and profilometr...
Article
Full-text available
We report on the effect of strain on the optical and structural properties of 5-, 10-, and 20-period GaN/AlN superlattices (SLs) deposited by plasma-assisted molecular beam epitaxy. The deformation state in SLs has been studied by high resolution transmission electron microscopy (HRTEM), X-ray diffraction, and micro-Raman, Fourier transform infrare...
Article
Manifestations of optical vibrations in thermoluminescence of organic polymers were observed. Thermoluminescence curves and Raman spectra of the polymers which have different degrees of ordering: poly (di-n-hexylsilane), poly(methylphenylsilane) and poly(di-n-penthylsilane) were measured and the features on thermoluminescence curves were observed....
Article
Using micro-Raman spectroscopy, a detailed study of vibrational spectra of L-Asparagine and L-Glutamine amino acids adsorbed on aluminum foils were carried out within the frequency range 80…3500 cm–1 under different excitation wavelengths. On the basis of detailed analysis of Raman spectra of the mentioned above amino acids and data of DFT-calculat...
Article
Using a new approach based on symmetry analysis, we have determined the magnetic symmetry groups (Shubnikov groups) of ferro- and antiferromagnetic wurtzite nanostructures doped with magnetic atoms periodically distributed at cation sites as well as the direction of the spontaneous magnetic field. Quantum wells, nanorods (nanowires), nanotubes, and...
Article
For the first time, we present a novel method of explosive evaporation (MEE) for the deposition of ZnO nanostructures using concentrated solar radiation for precursor evaporation. Zinc acetylacetonate powder and a mixture of ZnO with graphite powders are used as precursors for the deposition of ZnO nanostructures. ZnO nanostructures are deposited o...
Article
ZnO nanorods (NRs) arrays doped with a large concentration of Mn synthesized by aqueous chemical growth and were characterized by SEM, photoluminescence, Raman scattering, magnetic force microscopy (MFM). By comparison of spectra taken on pure and Mn-doped ZnO NRs, a few new Raman impurity-related phonon modes, resulting from the presence of Mn in...
Article
Electrical properties of low-threshold field emission cathodes produced by growth nanocluster graphene films on the pointed surface of heavily doped n⁺SiC by sublimation epitaxy have been considered. The quality of the graphene coating has been assessed based on the morphological studies and Raman spectroscopy. Using the volt–ampere characteristics...
Article
Full-text available
The energy spectrum of hole traps is investigated in organic polymer poly(di-n-hexylsilane) by the fractional thermally stimulated luminescence (TSL) in the 5–40 K temperature range. In addition, the Raman spectrum of the polymer is studied at 300 K. For the first time, the structure on a TSL curve is observed. It is found that the obtained activat...
Article
The influence of strain and barrier/well thickness ratio on recombination processes in multi-quantum well (MQW) Al0.1Ga0.9N/GaN structures was investigated using X-ray diffraction and Raman and photoluminescence spectroscopies. The deformation state of the wells and barriers was determined. In addition, the value of the polarization fields, the den...
Article
Full-text available
The effect of self-heating on the transport characteristics and electronic properties of transistor AlGaN/GaN heterostructures was investigated. The electrical, micro-Raman and photoluminescence techniques were used for temperature estimations for transistor structures under electrical load. The thermal resistance of these structures has been calcu...
Article
Full-text available
The effect of both CuO content (1 and 8 mol%) and calcination temperature (Tc = 500–1000◦C) on light emitting and structural properties of ZrO2-Y2O3-CuO nanopowders was studied by photoluminescence (PL), X-ray diffraction (XRD) and Raman scattering methods. The samples, calcinated at Tc = 500–700◦C, contain the tetragonal ZrO2 phase predominantly....
Article
Full-text available
The SERS (surface enhanced Raman spectroscopy) substrates based on nanocomposite porous films with gold nanoparticles (Au NPs) arrays were formed using the method of the pulsed laser deposition from the back low-energy flux of erosion torch particles on the glass substrate fixed at the target plain. The dependencies of porosity, and morphology of t...
Article
Full-text available
The SERS (surface enhanced Raman spectroscopy) substrates based on nanocomposite porous films with gold nanoparticles (Au NPs) arrays were formed using the method of the pulsed laser deposition from the back low-energy flux of erosion torch particles on the glass substrate fixed at the target plain. The dependencies of porosity, and morphology of t...
Article
Nanocomposite porous films with silver nanoparticle (Ag NP) arrays were prepared by the pulsed laser deposition from the back flux of erosion torch particles in argon atmosphere on the substrate placed at the target plane. Preparation conditions of the films were set by argon pressure, energy density of laser pulses, their amount and substrate posi...
Article
Samples of composite with ceramic matrix of aluminum nitride have been produced by pressureless sintering of the AlN-Y2O3 powder compositions with addition of SiC-C particles of size 50 nm (agglomerates of 200 nm). The presence of a SiC solid solution in AlN has been revealed by Raman and X-ray diffraction microanalyses and measurements of microwav...
Chapter
Structural and optical properties of pure and Y-doped ZrO2 nanopowders with different Y content sintered by co-precipitation of Zr and Y nitrates were investigated. It was observed that the increase of Y content stimulates the transformation of crystalline phase from monoclinic through tetragonal to cubic while the increase of calcinations time lea...
Article
It is demonstrated that surface-enhanced Raman scattering spectroscopy allows detecting 10–10М Rhodamine 6G (Rh 6G) on nanocomposite films containing silver nanoparticles with an amplification factor of 3 × 107. The films used for SERS, which exhibit gradients of thickness and have silver particles and pores of different size, were obtained by puls...
Chapter
Full-text available
Structural and optical properties of pure and Y-doped ZrO 2 nanopowders with different Y content sintered by co-precipitation of Zr and Y nitrates were investigated. It was observed that the increase of Y content stimulates the transformation of crystalline phase from monoclinic through tetragonal to cubic while the increase of calcinations time le...
Article
The SERS (surface enhanced Raman spectroscopy) substrates based on nanocomposite porous films with gold nanoparticles (Au NPs) arrays were formed using the method of the pulsed laser deposition from the back low-energy flux of erosion torch particles on the glass substrate fixed at the target plain. The dependencies of porosity, and morphology of t...
Article
Ternary Zn1–xCdxO (x < 0.12) alloy crystalline films with highly preferred orientation (002) have been successfully deposited on sapphire c-Al2O3 substrates using the direct current (dc) reactive magnetron sputtering technique and annealed at temperature 600°C in air. The structural and optical properties of Zn1-xCdxO thin films were systematically...
Article
Present work deals with the study of luminescence and structural properties of Y-doped ZrO2 nanopowders sintered by co-precipitation of Zr and Y nitrates. The structural and light emitting properties were controlled by X-ray diffraction, transmission electron microscopy, Raman scattering, photo- (PL) and cathodoluminescence (CL) methods. Generally,...
Article
Full-text available
The undoped and Cd-doped (0.4, 0.5 at. %) ZnO films deposited by radiofrequency magnetron sputtering have been irradiated by 167 MeV Xe26+ ions with energy to a fluence 3×1012 ions/cm2. The structure and vibrational properties of as-grown and irradiated samples were studied using X-ray diffraction and Raman spectroscopy techniques. It was found tha...
Article
ZnO-based compounds that exhibit a number of strongly overlapping emission bands in visible spectral region are promising materials for white-light emitters with continuous emission spectrum. Defect-related emission in doped with different impurities ZnO, however, spreads from green to red spectral region, so its shift toward shorter wavelengths is...
Conference Paper
Results of optical and electrical characterization of biased AlGaN/GaN HEMT nanostructures at different cryogenic and room temperatures are analyzed.
Article
The effect of laser radiation on the characteristics of amorphous silicon films on glassy or quartz substrates are studied by Raman spectroscopy. It is established that an increase in the laser-treatment power yields a phase transition from amorphous silicon to nanocrystalline silicon. The variation in the relation between the nanocrystalline and a...
Article
Full-text available
RF magnetron sputtering of two separate silicon and oxide (SiO2 or Al2O3) targets in pure argon plasma was used for deposition of Six(SiO2)1-x and Six(Al2O3)1-x films with x=0.15-0.7 on long fused quarts substrate. The effect of post-fabrication treatments on structural and light emitting properties of the films with different x values was investig...