X-ray Absorption Fine Structure study of nickel grains embedded in the carbonaceous films
|Mirosław Kozłowski 1,2, Robert Nietubyć 3, Elzbieta Czerwosz 1,4, Ryszard Diduszko 1,2,5, Piotr Dłużewski 2, Joanna Rymarczyk 1, Edmund Welter 6|
1. Industrial Institute of Electronics (PIE), Dluga, Warszawa 00-241, Poland
We have measured Ni K-edge extended x-ray absorption fine structure (EXAFS) spectra for 300 nm thick carbonaceous films containing Ni clusters of the size in the range 2‑20 nm The films with various nickel concentrations have been deposited onto a Mylar® foil substrate by PVD method. EXAFS measurements have been performed in fluorescence and transmission mode at the A1 beamline at DORIS III in Hamburg.
The EXAFS spectra were interpreted by fitting calculated scattering paths contributions to the experimental contributions extracted from the measured fine structure by Fourier Transform filtering. The analysis was supported by ab initio model calculations (FEFF) performed for distorted fcc structures and structures optimized for Ni13 clusters.It has been found that for none of the studied samples the range of crystalline order exceeded 5 neighboring shells (6 Å). Spectra measured for the samples containing the most diluted nickel showed an enhanced white line and other spectral features which are not observed for metallic bulk nickel. For samples having Ni concentration of 2.7 wt% the crystalline order has been found to be limited to the nearest neighbors.
Presentation: Poster at E-MRS Fall Meeting 2007, Symposium I, by Mirosław Kozłowski
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-05-15 15:09 Revised: 2009-06-07 00:44