Univ Sci & Technol China, Natl Synchrotron Radiat Lab, Hefei 230029, Anhui, Peoples R China
; Univ Sci & Technol China, Dept Phys, Hefei 230026, Anhui, Peoples R China
; Chinese Acad Sci, Inst High Energy Phys, Beijing 100039, Peoples R China
; Anhui Univ, Dept Phys, Hefei 230039, Anhui, Peoples R China
; Capital Normal Univ, Dept Phys, Beijing 100037, Peoples R China
Nanostructured zirconia doped with 5% yttria was prepared by a co-precipitate method. The structures were characterized by x-ray diffraction and extended x-ray absorption fine structure spectroscopy. The sample calcined at 300degreesC had an amorphous phase and a local structure like cubic zirconia. It crystallized into tetragonal nanocrystalline zirconia at 500degreesC and the monoclinic phase appeared at 900degreesC. The Y atoms merged into the zirconia network at 300degreesC, with the oxygen vacancies located around the Zr atoms. The coordination number of the cation-cation reduction is due to the large amount of cations near the surface with fewer nearest neighbours when the grain size decreases.