EXAFS studies of doped-ZrO 2 systems

Abstract

Extended X-ray absorption fine structure (EXAFS) spectroscopy measurements have been carried out on a number of 5% rare earth-doped ZrO 2 materials, where the dopant cations used were Er 3+, Gd 3+ and La 3+. It has been found that the nature of the dopant cation influences the location of the promoted oxygen vacancies. In the case where a relatively small dopant cation is used, e.g. Er 3+, the vacancies are located in the vicinity of the host Zr 4+ cation. However, in the situation where a much larger impurity cation was used, e.g. La 3+, the oxygen vacancies are situated in the proximity of the dopant cation. In conjunction with these EXAFS results, conductivity measurements made on these systems provide further evidence that the nature of the dopant cation can play a major role in determining the conductivity characteristics of these materials.