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Using the method of X-ray diffraction, the effect of shock-vibration treatment on the structural parameters and phase composition of mixtures of silicon dioxide and alpha iron oxide was studied. From these results, has been found that the shock-vibration treatment of oxides mixture leads to an increase in the coherent scattering region of crystalline α-Fe2O3. We obtained SEM images of composites before and after treatment. From the SEM images it is seen that the processing is accompanied by fragmentation of the aggregates, uniform placement of the nanoparticles between each other and the formation of new denser agglomerates. Electron-microscopic study of mixtures using TEM was performed, which showed that the treatment leads to a lay-up of particles each other with the formation of interatomic interaction between them, which is consistent with the results of ultra-soft X-ray emission spectroscopy. The electrochemical properties of LPS, with electrodes based on mixtures before and after treatment, in galvanostatic mode were investigated. It is found that the charge capacity of the LPS with the electrode based on the mixture with the maximum concentration of α-Fe2O3 after treatment is reduced by half. In addition, such LPS doesn’t have the following cycling, which is most likely to be associated with an increase inthe recombination probability of lithium ions on the surface of the electrode material due to the increase in the population of Op-electrons near the Fermi level and compaction of the nanocomposite.

Ultra-soft X-ray emission spectroscopy was used to study the distribution of Op-, Sisd- and Alsd- valence electrons in (SiO2)x(Al2O3)1-x (x = 0.8, x = 0.7) powder mixtures after mechanical treatment. An increase in atomic charges has been measured and can be explained by the transfer of electrons from Si/Al to O atoms in split Opπ-binding states and the formation of the weak long (O O)π bonds between the surface atoms of the contacted powder nanoparticles. Scanning and transmission electron microscopy images show an enhanced agglomeration of the nanoparticles of both SiO2 and Al2O3 oxides, but no changes in the crystalline parameters have been measured using X-ray diffraction. An increase in charge capacities of lithium ion power sources with 0.8SiO2–0.2Al2O3 electrode has been observed during cycling. At the same time, a decrease of the charge capacities with the 0.7SiO2–0.3Al2O3 electrode has been measured. The results are discussed in terms of an increase in the binding energy of electrons in the Op-states, which prevents the recombination and irreversible reactions of lithium with electrode atoms. Otherwise, due to cycling, electron population increase of in non-binding states near the valence band top contributes to the recombination ability of Li+ ions and leads to a decrease in the charge capacity.

Електронна структура нанокомпозитів SiO2/TiO2/C досліджена методом ультрам’якої рентгенівської емісійної спектроскопії (УМРЕС). Енергетичний перерозподіл валентних електронів в гібридних SiO2/TiO2/C матеріалах було вивчено в залежності від складу. Були отримані УМРЕС SiLα-, CKα- та ОKα-спектри SiO2/TiO2 та SiO2/TiO2/С сполук. Було виявлено, що майже всі двофазні оксиди проникають у пори вуглецю після високочастотного вібраційного синтезу в композиті ST65+C (50 мас % C, 17.5 мас % SiO2, 32.5 мас % TiO2). Було показано, що проникнення TiO2 у високопористий вуглець більше, ніж SiO2. Було виявлено, що кисень, який відноситься до TiO2, не утворює зв’язків з атомами вуглецю. Було встановлено, що вклад s-станів в нанокомпозиті ST20+C (50 мас % C, 40 мас % SiO2, 10 мас % TiO2) зростає у порівнянні з ST20 (80 мас % SiO2, 20 мас % TiO2) завдяки додаванню Cs-станів вуглецю. Було показано, що SiC формується в нанокомпозиті ST65+C завдяки заміщенню атомів кисню атомами вуглецю у присутності TiO2, як каталізатора. Дослідження електронної структури нанокомпозитів SiO2/TiO2/C дозволяє вирішити важливу задачу передбачення їх фізичних та хімічних властивостей та синтезувати матеріали з необхідними властивостями. The electronic structure of SiO2/TiO2/C nanocomposites was investigated using the ultrasoft X-ray emission spectroscopy (USXES) method. The energy redistribution of valence electrons affected by composition of SiO2/TiO2/C hybrid materials was studied. The USXES SiLα-, CKα- and ОKα-spectra for the SiO2/TiO2 and SiO2/TiO2/C compounds were derived. It was revealed that almost all two-phase oxides penetrate to carbon pores in the ST65+C (50 wt. % C, 17.5 wt. % SiO2, 32.5 wt. % TiO2) nanocomposite after high-frequency vibration synthesis. It was shown that penetration of TiO2 to highly porous carbon is higher than SiO2. It was found that oxygen related to TiO2 does not form bonds with carbon atoms. It was revealed that the contribution of s-states in ST20+C (50 wt. % C, 40 wt. % SiO2, 10 wt. % TiO2) nanocomposite increased as compared to ST20 (80 wt. % SiO2, 20 wt. % TiO2) owing to carbon Cs-states addition. It was shown that SiC is formed in ST65+C nanocomposite owing to substitution of oxygen atoms by carbon atoms in the presence of TiO2 as a catalyst. Investigation of the electronic structure of SiO2/TiO2/C nanocomposites allows solving an important task of predicting their physical and chemical properties and synthesising materials with necessary properties.

Crystalline and electronic structures of SiO2/Al2O3 mixtures have been analyzed using X-ray diffraction (XRD) and ultra-soft X-ray emission spectroscopy (USXES). Comparison of ultrasoft X-ray emission AlLα-, SiLα- and OKα-bands redistribution Alsp-, Sisp- and Op-valence electrons when changing the mass ratio (0,23Al2O3+0,77 SiO2;, 0,30Al2O3+0,70SiO2; 0,75Al2O3+25 SiO2) and depending on the method of obtaining them. Expansion OKα-emission bands showed an increase in population of Opπ-levels of oxygen in the formation of pyrogenic composites with different contents of aluminum oxide and silicon dioxide. Analysis AlLα-, SiLα- emission bands allowed to explain the increase of population Opπ-levels of oxygen and present the morphology formation of particles different of pyrogenic composites during synthesis.

Crystalline and electronic structures of SiO2/γ-Fe2O3 mixtures have been analyzed using X-ray diffraction (XRD) and ultra-soft X-ray emission spectroscopy (USXES). The energy redistribution of Fesрd, Sisp and Op valence electrons due to changes in the mass ratio (0,2 SiO2 + 0,8 γ-Fe2O3 , 0,5 SiO2 + 0,5 γ-Fe2O3, 0,8 SiO2 + 0,2 γ-Fe2O3) of SiO2 and α-Fe2O3 in the mixtures has been studied. The FeLα, SiLα and OKα ultra-soft X-ray emission spectra of SiO2/α-Fe2O3 mixtures were compared with those of individual iron oxide and silica powders. In analyzing these bands were detected shape similarity and the presence of identical elements of fine structure in OKα and FeLα-emission spectra, it shows a high degree of hybridization and Op- Fe3d - electronic valence states. Expansion OKα and FeLα-emission bands in the low energy side is the result of additional splitting energy Op- and Fe3d - levels with increasing degree of hybridization in the mehanoaktyvatsiynoyi processing.

Using the method of electrochemical analysis the charge capacity of electrochemical cells with cathode material on the bases of simple and mechanically activated mixtures 0,2α-Fe2O3+0,8Al2O3, 0,2α-Fe2O3+0,8SiO2 та 0,2γ-Fe2O3,8SiO2 has been researched. With the help of method of ultra soft X-ray spectroscopy the influence of mechanical activation method on the distribution of valence electrons of these mixtures has been researched. In this research, the relationship between changes in populations of electronic states in the valence band and intercalation properties of studied mixtures has been studied. Keywords: γ-Fe2O3, α-Fe2O3, SiO2, Al2O3, mechanical activation, the energy redistribution, ultra-soft X-ray emission spectroscopy (UMRES), electrochemical analysis, phase composition, coherent scattering region.

Crystalline and electronic structures of nanoalumina alone and in different mixtures with nanosilica have been analyzed using X-ray diffraction (XRD) and ultrasoft X-ray emission spectroscopy (USXES). Narrowing of the OK α bands of crystalline alumina occurs with decreasing nanoparticle size. Electron transfer from oxygen to aluminum atoms due to Al–O bond breakage under irradiation leads to occupation of high-energy 3d level of Al. In nanoparticles, the Al–O bond strength and O–O interactions enhanced by Laplace (bubble) pressure lead to δ phase stabilizing if coherent-scattering region size (d CSR ) reaches 7 nm which is smaller than that for θ phase (d CSR = 11–20 nm) of alumina and silica/alumina studied. The d CSR values are in agreement with nanoparticle sizes calculated using self-consistent regularization method applied to nitrogen adsorption data.

Investigations of graphene nanosheets and oxidized graphene nanosheets were carried out using X-rayphotoelectron spectroscopy. Scanning and transmission electron microscopy investigations were used in additionto X-ray photoelectron spectroscopy. It was found that functional carboxyl and epoxide groups were removedfrom samples due to argon bombardment in studies of oxidized graphene nanosheets with X-ray photoelectronspectroscopy. Thus the ОKα-band was not revealed in oxidized graphene nanosheets owing to oxygen removaldue to electron bombardment with the use of. ultra-soft X-ray emission spectroscopy. Keywords: X-ray photoelectron spectroscopy, electronic structure, graphene nanosheets, oxidized graphenenanosheets.

Fumed silica, initial alumina blend, after mechanochemical activation (MCA), and fumed binary silica/alumina (SA) were studied using infrared spectroscopy, X-ray diffraction (XRD), ultrasoft X-ray emission (USXE) spectroscopy (giving emission bands Si Lα, Al Lα and O Kα related to valence electron transfer onto core levels) and quantum chemistry. The MCA influence on nanoparticle characteristics (sizes, electronic structure) increases with increasing alumina content in the blends due to stronger abrasive effect of alumina nanocrystallites (snagging a surface layer of nanoparticles during MCA) than non-crystalline silica nanoparticles. A difference in Si Lα, Al Lα and O Kα affected by MCA increases with increasing alumina content. It is greater for the top peak of the upper valence band (UVB) than for a lower energy peak in the bottom of the UVB. These spectral changes suggest redistribution of electron density between Si, Al and O atoms depending on alumina content, material type and treatment conditions. The main difference in the properties of the SA blends and binary SA is due to distribution of Si atoms in alumina phase and Al atoms in silica phase in fumed SA (which is amorphous at CAl2O3 ≤ 30 wt.%) in contrast to the SA blends with practically separated silica and alumina nanoparticles.

Nanosilicas (A-50, A-300, A-500)/activated carbon (AC, SBET = 1520 m2/g) composites were prepared using short-term (5 min) mechanochemical activation (MCA) of powder mixtures in a microbreaker. Smaller silica nanoparticles of A-500 (average diameter dav = 5.5 nm) can more easily penetrate into broad mesopores and macropores of AC microparticles than larger nanoparticles of A-50 (dav = 52.4 nm) or A-300 (dav = 8.1 nm). After MCA of silica/AC, nanopores of non-broken AC nanoparticles remained accessible for adsorbed N2 molecules. According to ultra-soft X-ray emission spectra (USXES), MCA of silica/AC caused formation of chemical bonds Si–O–C; however, Si–C and Si–Si bonds were practically not formed. A decrease in intensity of OKα band in respect to CKα band of silica/AC composites with diminishing sizes of silica nanoparticles is due to both changes in the surface structure of particles and penetration of a greater number of silica nanoparticles into broad pores of AC microparticles and restriction of penetration depth of exciting electron beam into the AC particles.

Morphological, structural, electronic, and adsorption characteristics of complex oxides such as fumed silica/alumina and silica/titania, fumed silica with deposited oxides of Mg, Ti, Mn, Ni, Cu, Zn and Zr, silica gel with grafted ZrO 2 , sol–gel titania doped by 3d-metals (Cr, Fe, Mn, V) were compared using adsorption, TEM, AFM, XRD, XPS, Mossbauer and Raman spectroscopy data. It was shown that surface, volume, and phase compositions of oxides, particle size distributions (5 nm–3 μm), specific surface area ( S BET ∼ 50–500 m 2 /g), and porosity ( V P ∼ 0.1–2 cm 3 /g) affected by synthesis technique and subsequent treatment determine electronic structure (bandgap, valence band and core levels structure) of the materials, adsorption of molecules and metal ions as well as other characteristics.