EXAFS as a tool for catalyst characterization: a review of the ... - INT

Therefore, the EXAFS analysis demonstrated that the alloy phase was
formed during reduction, as already shown by magnetic and X-ray
diffraction measurements (Noronha, 1994). The bimetallic particles
consist of both palladium and cobalt rich phases.
CONCLUSIONS
A review of the EXAFS data analysis methods was presented. A
detailed description of the EXAFS signal extraction and the Fourier
transform of the data were discussed. The procedure for determining
interatomic distances, coordination numbers and disorder effects
from EXAFS data was described. These parameters were calculated in
order to obtain both further evidence of Pd-Co interaction and the
mean composition of bimetallic particles.
NOMENCLATURE
Aj(κ ) the backscattering amplitude from each of the N j neighboring
atoms
E photoelectron energy
E 0 energy of the absorption edge
Planck`s constant divided by 2π
h.ν energy of the X-ray photon
I 0 photon intensities before the absorber
I photon intensities after the absorber
m mass of the electron
N j number of atoms in the j th shell
N ind number of independent points
N par number of parameters
p i fitting parameters