XRD study of the local structure and phase composition of catalysts with use of synchrotron radiation: Method of the radial distribution of electron density

Some examples illustrating the use of the method based on the radial distribution function (RDF) of electronic density for investigation metal and oxide catalysts are reported. Using monoatomic unsupported metal catalysts with crystallite sizes D=40–450 Å, it was shown that the areas of coordination peaks in RDF directly define the absolute values of coordination numbers Z and depend on crystallite sizes. The investigation of the phase composition and local structure of supported metal catalysts revealed that the interaction between the active component and the support was responsible for the thermal stability of small supported metal particles. The local structure of ceria with different crystallite sizes was investigated.