Local structure analyses of Ce0.5Zr0.5O2 mixed oxides by XAFS

Abstract

Three types of CeO2-ZrO2 with the same composition (Ce/Zr = 1) were prepared by different methods, exhibited the different oxygen storage/release capacity (OSC). To investigate the relationship between the OSC and the local structure, the Ce and Zr K-edges XAFS spectra for these samples were measured. The features of Fourier transforms of these samples were different from each other. This suggested that the OSC was remarkably exerted by the local structure around Ce and Zr. The quantitative curve-fitting analysis of EXAFS was applied, and it was concluded that homogeneous Ce0.5Zr0.5O2 solid solution at atomic level exhibited the highest OSC among these CeO2-ZrO2 with the same composition (Ce/Zr = 1).