A5107071019- ZnO doping and properties
- Advanced ceramic materials synthesis
- Advanced materials and composites
- Gas Sensing Nanomaterials and Sensors
- Boron and Carbon Nanomaterials Research
- Catalytic Processes in Materials Science
- Microwave Dielectric Ceramics Synthesis
- Ga2O3 and related materials
- Silicon Nanostructures and Photoluminescence
- Magnesium Oxide Properties and Applications
- Quantum Dots Synthesis And Properties
- Advancements in Solid Oxide Fuel Cells
- Catalysis and Oxidation Reactions
- Semiconductor materials and devices
- Semiconductor materials and interfaces
- Chalcogenide Semiconductor Thin Films
- Magnetic and transport properties of perovskites and related materials
- Copper Interconnects and Reliability
- Mechanical and Optical Resonators
- Intermetallics and Advanced Alloy Properties
- Copper-based nanomaterials and applications
- Solid-state spectroscopy and crystallography
- Crystal Structures and Properties
- Pigment Synthesis and Properties
- Electrical and Thermal Properties of Materials
V.E. Lashkaryov Institute of Semiconductor Physics
2013-2024
National Academy of Sciences of Ukraine
2014-2024
Institute of Physics
2014
Abstract The Raman spectra of surface regions bulk Cu 2 ZnSnS 4 (CZTS) samples with different and Zn cation content were obtained the differences in are attributed to statistical disorder effects sublattice. This sublattices may initiate a change crystal symmetry from kesterite‐type $({I\bar 4})$ 42m})$ space group. investigated CZTS crystals grown at high temperature characterised by co‐existence composition ratio Cu/(Zn + Sn) which results kesterite disordered phases. presence phase...
Abstract Undoped and Mn-doped ZnO ceramics were prepared from the powders compacted at different pressures sintered in air high temperature. Their structural, optical, light emitting electrical characteristics as well distribution of chemical elements studied. It was found that an increase compacting pressure stimulates direct current conductivity both undoped doped samples. In case samples, this effect accompanied by a decrease height potential barriers grain boundaries. is electron...
Ge-rich ZrO2 films, fabricated by confocal RF magnetron sputtering of pure Ge and targets in Ar plasma, were studied multi-angle laser ellipsometry, Raman scattering, Auger electron spectroscopy, Fourier transform infrared X-ray diffraction for varied deposition conditions annealing treatments. It was found that as-deposited films are homogeneous all contents, thermal treatment stimulated a phase separation formation crystalline ZrO2. The “start point” this process is the range 640–700 °C...
The structural and electrical characteristics of (Mg,Zn)O ceramics produced using the solid state reaction at 1100 °C for 3 hours were studied applying X-ray diffraction IR reflection spectroscopy as well means direct current measurements versus MgO content in initial charge (varied from 0 to 100 mol.%). It has been shown that conductivity extracted spectra corresponds hexagonal phase a solution, while plasmon cubic was not observed. electron concentration grains solution prepared with below...
Abstract Undoped, Cu and/or Y doped ZrO 2 nanopowders were synthesized with Zr, Y, and nitrates using a co-precipitation approach. Their structural optical properties examined regarding dopant content (0.1–8.0 mol.% of CuO 3–15 O 3 ) calcination conditions (400 °C–1000 °C and, 1,2 or 5 h) through Raman scattering, XRD, TEM, EDS, AES, EPR, UV–vis FTIR diffused reflectance methods. The results showed that both dopants promoted the appearance additional oxygen vacancies in host, while formation...
The effect of the milling virgin ZnO and MgO powders on structural, optical, electrical properties Mg 0.2 Zn 0.8 O ceramics is studied. In all ceramics, both cubic hexagonal phases solid solution are formed simultaneously. phase represented by densely sintered grains that doped with magnesium homogeneously. crystallites turn out to appear in large pores. infrared reflection spectra show intial does not affect free carrier concentration grains. It found be close being determined interstials....
The influence of chlorine on spatial distribution subvalent dopants and oxygen vacancies' content in Cu-doped Y-stabilized ZrO2 nanopowders was studied as a function calcination temperature (500-1000°C) Cu (1 8 mol %). powders were prepared by co-precipitation technique from mixture zirconium oxychloride, yttrium copper nitrates. X-ray diffraction, Auger spectroscopy, attenuated total diffuse reflectance, well electron paramagnetic resonance methods. increase stimulates structure...
The ZnO–Li films were synthesized and investigated in an attempt to explore develop RE-free phosphor materials capable of emitting intense visible light a wide spectral range. effects both heterovalent doping with lithium high-temperature annealing on the optical properties ZnO studied. deposited Al 2 O 3 substrate using screen-printing method annealed at 800–1,000°C air for 0.5–3 h. Both result transformation shape reflectance spectra range 300–400 nm shift absorption edge long-wavelength...
The structural characteristics, chemical composition, and element spatial distribution in MgxZn1-xO ceramics were investigated using X-ray diffraction, scanning electron microscopy, Auger spectroscopy, energy-dispersive cathodoluminescence techniques. study revealed that the morphology of ceramic samples, as well mechanism solid solution formation, depend on relative contribution both oxides charge. It was discovered hexagonal cubic phases found to form simultaneously. An increase MgO...
The object of research is the effect sintering under pressure (10 MPa–4.1 GPa) on formation structure and properties ZrB2, HfB2, composites their bases. It has been found that high consolidation results in an improvement mechanical characteristics. In particular, hardness fracture toughness materials sintered 4.1 GPa are higher than those obtained hot pressing conditions at 20–30 MPa spark-plasma 50 MPa.High-pressure HfB2 demonstrated HV(9.8 N)=21.3±0.8 GPa, HV(49 N)=19.3±1.3 HV(98...
The object of research is HfB2, ZrB2 and ceramics composition HfB2-30 % SiC ZrB2-20 SiC, SiC-4 Si3N4 obtained under high pressure, their mechanical characteristics before after heating to temperatures beginning melting. was conducted in order create new effective refractory materials for use the aerospace industry. Therefore, melting sintered effect on properties were also studied. Additives (ZrB2-20 SiC) although led a decrease specific gravity. But increased hardness (by 17 46 case...
The influence of compacting pressure on the structural, optical, light emitting and electrical characteristics as well morphology chemical element distribution for undoped Mn-doped ZnO ceramics has been studied. For ceramics, increase direct current conductivity with was found being accompanied by disappearance its temperature dependence in samples compacted at 150 MPa. samples, it observed not only conductivity, but also decrease superlinearity current-voltage (that is known to be features...
Mn-doped ZnO, MgO and Zn0.75Mg0.25O samples ([Mn] = 0.1 at.%) were produced by conventional solid-state technique investigated means of XRD, EPR, absorption, photocurrent, photo- cathodoluminescence methods. It was shown that solid solution with hexagonal structure has the bandgap Eg ∼3.65 eV. The quenching host defect-related luminescence in ZnO:Mn Zn0.75Mg0.25O:Mn observed, while Mn-related emission being absent. energy level MnZn2+ center found to be at 2.16 eV below conduction band...