Local structure of the metal-oxygen bond in compositionally homogeneous, nanocrystalline ZrO2-CeO2 solid solutions synthesised by a gel-combustion process

I.O. FÁBREGAS; R.O. FUENTES; D.G. LAMAS; M.E. FERNÁNDEZ DE RAPP; N.E. WALSÖE DE RECA; M.C.A. FANTINI; A.F. CRAIEVICH; R.P. MILLEN; M.L.A. TEMPERINI

JOURNAL OF PHYSICS CONDENSED MATTER

Elsevier

Año: 2006 vol. 18 p. 7863 - 7881

0953-8984

Compositionally homogeneous ZrO2-CeO2 nanopowders have been characterized by Raman and extended x-ray absorption fine structure (EXAFS) spectroscopies. These techniques revealed a tetragonal-to-cubic phase transition as a function of CeO2 content, as observed in a previous synchrotron x-ray diffraction study. The tetragonal-cubic phase boundary was found to be at (85 ± 5) mol% CeO2. The EXAFS study demonstrated that this transition is related to a tetragonal-to-cubic symmetry change of the Zr-O first neighbour coordination sphere, while the Ce-O coordination sphere preserves its cubic symmetry over the whole composition range.