In situ EXAFS study of the alloy catalyst Pd-Co (50%/50%)/SiO2

In situ extended X-ray absorption fine structure (EXAFS) data for nanocrystalline bimetallic Pd-Co catalyst supported on silica, for Pd K and Co K absorption edges, are presented and analysed confirming previously developed atomistic model of segregation within the alloy metal particle. Supporting evidence is presented from dynamical X-ray diffraction (DXRD) data. The confirmed segregation model concerns energy minimised partial surface segregation of Pd in contrary to a complete segregation model that does not fit well the EXAFS data. (C) 1999 Elsevier Science S.A. All rights reserved.