CuXWCNT (X = Cl, Br, I) nanostructures were prepared by capillary filling of 1.4a1.6 nm single-walled carbon nanotubes (SWCNT) with copper halides. The structure of CuXWCNT (X = Cl, Br, I) represents ...a distorted two-layer hcp of halogen atoms arranged along the SWCNT. The EXAFS and the high angle angular dark field (HAADF) HRTEM data indicate that Cu is partially coordinated by C. According to the optical absorption, valence band photoemission spectroscopy and work function measurements, a Fermi level (FL) downshift as compared with the initial value for the nanotubes and a corresponding charge transfer from the nanotubes to the 1D crystals is observed for CuXWCNT nanostructures. The FL shift increases in the sequence CuI < CuBr < CuCl due to an increase of the electron affinity for the halogen atoms. The XPS data confirm the acceptor effect of copper halides and indicate that metallic and semiconducting nanotubes behave differently. Raman spectroscopy performed under electrochemical charging allowed estimation of the value of charge transfer between the nanotube walls and the intercalated 1D crystal. The X-ray absorption and emission spectra for carbon and copper thresholds revealed a new energy level composed of the carbon 2Nz and copper 3d-orbitals. This indicates the CuaC bonding, which in line with the structural HAADF HRTEM and EXAFS data.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
X-Ray absorption near-edge structure (XANES) spectra at the Ti K-edge of TiO(2) (rutile and anatase phases) have been analyzed. Theoretical analyses of the experimental data have been performed on ...the basis of both real-space full multiple scattering theory with muffin-tin approximation for potential shape and full-potential (beyond muffin-tin approximation) finite difference method. A full potential is required to satisfactorily reproduce experimental Ti K-edge XANES spectra in the TiO(2).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
X-Ray absorption near-edge structure (XANES) spectra at the Ti
K-edge of TiO
2 (rutile and anatase phases) have been analyzed. Theoretical analyses of the experimental data have been performed on the ...basis of both real-space full multiple scattering theory with muffin-tin approximation for potential shape and full-potential (beyond muffin-tin approximation) finite difference method. A full potential is required to satisfactorily reproduce experimental Ti
K-edge XANES spectra in the TiO
2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The decomposition of Pt(acac) sub(2) in H sub(2) induced by flash heating was investigated. The changes in the local Pt structure were followed using in situ high energy resolution off-resonant ...spectroscopy (HEROS). The metal complex was flash heated to 150 degree C and HEROS spectra were collected every 500 ms. The Pt(acac) sub(2) decomposition was shown to consist of a two-step reduction process of the Pt (II) species.
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