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In present work the properties of iron-doped indium tin oxide (ITO) films with reduced to 50 mass% indium oxide content prepared by co-sputtering of ITO and Fe2O3 targets and ITO and Fe3O4 targets in mixed argon–oxygen atmosphere were studied by various methods. The influence of different working gas flow rates, RF power of iron oxide targets, type of doping oxide and heat treatment temperatures on the electrical, optical, structural, and morphological properties of the films was characterized by means of four-point probe method, ultraviolet–visible (UV–Vis) spectroscopy, X-ray diffraction and atomic force microscopy. [ABSTRACT FROM AUTHOR]

Silicon nano- and microparticles obtained using electric-spark dispersion of silicon electrodes and granules in 40 wt% solution of methyl alcohol in water were investigated by ultrasoft X-ray emission spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning and transmission electron microscopies. In addition, the SiLα spectra of obtained silicon particles were modeled by superimposing the spectra of pure silicon and silicon oxide taken in certain weight ratios. It was found that the surfaces of Si nano- and microparticles obtained in 40 wt% solution of methyl alcohol in water are covered with silicon oxide and chemisorbents, while the core consists of crystalline silicon with a cubic face-centered lattice. The silicon nano- and microparticles show potential as an anode material to replace commonly used graphite electrodes. The charge capacity of the electrode based on mixture of Si nano- and microparticles with graphite powder was about 1272 mAh/g after ten cycles. [ABSTRACT FROM AUTHOR]

Composites based on Zr65Cu17.5Ni10Al7.5/PTFE (polytetrafluoroethylene) with silane were prepared by ball milling with subsequent thermal pressing. Silanization was performed in the alcoholic solution with metallic glass powder. Different composites, 30/70 and 50/50 with silane, were prepared. During ball milling, Zr2Cu and Zr2Ni intermetallic phases were formed. The Zr-based metallic glass had a large supercooled region, and the melting point of the 30/70 and 50/50 composites with silane was near to the melting point of PTFE. The 50/50 composite (silane) had the highest thermal conductivity compared to the 30/70 composite samples. The incorporation of silane in metallic glass/polymer was investigated by Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) analysis. Thermogravimetric analysis (TGA) showed the thermal stability of the composite samples up to 450–460 °C. It was also concluded that the 50/50 composite with silane has better thermal stability than the 30/70 composite with silane. The addition of silane in 30/70 and 50/50 composites increased the thermal conductivity compared to the composites without silane. [ABSTRACT FROM AUTHOR]

Multilayer iron-doped indium-saving indiumtin oxide (ML ITO50:Fe2O3) thin films with high conductivity and high transmittance in the visible spectrum have been fabricated by sputtering method. Structures consisting of very thin layer of conventional indium tin oxide (90 mass% In2O310 mass% SnO2) and iron-doped indium-saving indiumtin oxide layer with reduced content of In2O3 (ITO50:Fe2O3) to 50 mass% are discussed. By optimizing oxygen flow rate in iron-doped indium-saving indiumtin oxide layer, the lowest volume resistivity of 3.78 × 10-4·cm, mobility of 29.8cm2/(V·s), carrier concentration of 4.60 × 1020 cm-3 and transmittance larger than 90% in the visible range have been achieved. ML ITO50:Fe2O3 thin films deposited under optimal conditions demonstrated lower volume resistivity and higher transmittance than undoped multilayer indium-saving ITO thin films and iron-doped single-layer thin films obtained under the same oxygen flow rate Q(O2) = 0.1 sccm. ML ITO50:Fe2O3 thin films demonstrated optimal parameters at the lower oxygen flow rate (Q(O2) = 0.1 sccm) than undoped ML ITO50 thin films. ML ITO50:Fe2O3 thin films are crystallized and show In4Sn3O12 structure. [ABSTRACT FROM AUTHOR]

Hollow graphitic carbon nanoparticles (HGCNs) obtained by catalytic graphitization of acetylene carbon black (ACB) were investigated using ultra-soft X-ray emission spectroscopy. The electronic structures of the ACB HGCNs were compared with those of HGCNs obtained from iron carbide-filled carbon nanocapsules (Fe3C@CNCs) and Q-graphenes. The occupation of the π sub-band decreased in the following sequence: Fe3C@CNC HGCNs > ACB HGCNs > Q-graphenes. This sequence can be explained by changes in the occupations of the C2p states due to the formation of bonds between carbon and residual metal atoms within the HGCNs. It was also found that the contribution of the overlapping ofppπ+ppσ-states in the ACB HGCN walls toward the spectra of the HGNCs was greater in comparison with the reference Q-graphenes. It was established that ACB was not fully transformed into the HGCNs. Scanning and transmission electron microscopy methods were used to study the spatial structures and morphologies of the fabricated HGCNs. [ABSTRACT FROM PUBLISHER]

For the first time Fe–Pt alloy included carbon nanocapsules were synthesized by an electric plasma discharge in an ultrasonic cavitation field of liquid ethanol. This contrasts the extensively used chemical synthesis methods which produce uncoated Fe–Pt alloy nanoparticles. We proposed that the as-synthesized Fe–Pt alloy included carbon nanocapsules are potentially useful in biomedical applications. Thereby an aim of this work was to coat the Fe–Pt alloy nanoparticles by graphite shells using plasma discharge in liquid ethanol and to study the structure and magnetic properties of the carbon encapsulated Fe–Pt alloy nanoparticles. The core–shell structured nanoparticles were characterized by transmission electron microscopy and X-ray diffraction. These methods revealed the presence of a disordered face-centered cubic (fcc) structure ( γFe, Pt) in the cores of the as-synthesized carbon nanocapsules. The as-synthesized carbon nanocapsules showed the soft magnetic character at room temperature. These carbon nanocapsules may provide a new approach in the transport and delivery of anticancer drugs. [ABSTRACT FROM AUTHOR]

Amorphous aluminum-doped indium tin oxide (ITO) thin films with a reduced indium oxide content of 50 mass% were manufactured by co-sputtering of ITO and Al2O3 targets in a mixed argon–oxygen atmosphere onto glass substrates preheated at 523 K. The oxygen gas flow rate and heat treatment temperature effects on the electrical, optical and structural properties of the films were studied. Thin films were characterized by means of a four-point probe, ultraviolet–visible-infrared (UV–Vis-IR) spectroscopy and X-ray diffraction. Transmittance of films and crystallization temperature increased as a result of doping of the ITO thin films by aluminum. The increase in oxygen flow rate led to an increase in transmittance and hindering of the crystallization of the aluminum-doped indium saving ITO thin films. It has been found that the film sputtered under optimal conditions showed a volume resistivity of 713 µΩ cm, mobility of 30.8 cm2/V·s, carrier concentration of 2.9 × 1020 cm−3 and transmittance of over 90% in the visible range. [ABSTRACT FROM AUTHOR]