EXAFS study of doped ceria using multiple data set fit

EXAFS analysis was applied to ceria compounds doped with Gd3+, Y3+ and La3+. Although several studies using EXAFS have been reported, their analysis was limited only to the nearest neighbor shell. We analyzed the next nearest neighbor shell using "multiple data set fit" method, where two EXAFS data sets of the same sample around Ce4+ and dopant cation were fitted at the same time. Based on the EXAFS results, local structure of the doped ceria compounds was discussed. It was found that Y3+ and La3+ had a strong tendency to get together and formed a dopant-rich cluster including oxygen vacancies, whereas Gd3+ did not gather and distributed randomly in ceria lattice. (c) 2005 Elsevier B.V. All rights reserved.