Tetragonal-cubic phase boundary in nanocrystalline ZrO(2)-Y(2)O(3) solid solutions synthesized by gel-combustion

By means of synchrotron X-ray powder diffraction (SXPD) and Raman spectroscopy, we have detected, in a series of nanocrystalline and compositionally homogeneous ZrO(2)-Y(2)O(3) solid solutions, the presence at room temperature of three different phases depending on Y(2)O(3) content, namely two tetragonal forms and the cubic phase. The studied materials, with average crystallite sizes within the range 7-10 nm, were synthesized by a nitrate-citrate gel-combustion process. The crystal structure of these phases was also investigated by SXPD. The results presented here indicate that the studied nanocrystalline ZrO(2)-Y(2)O(3) solid solutions exhibit the same phases reported in the literature for compositionally homogeneous materials containing larger (micro)crystals. The compositional boundaries between both tetragonal forms and between tetragonal and cubic phases were also determined. (C) 2011 Elsevier B.V. All rights reserved.

Brazilian Synchrotron Light Laboratory (LNLS, Brazil)[D12A-XRD1-1857]

Brazilian Synchrotron Light Laboratory (LNLS)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

CNPq (Brazil)[490289/2005-3]

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

CNPq (Brazil)[490580/2008-4]

Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT)

ANPCyT Agencia Nacional de Promocion Cientifica y Tecnologica (Argentina)[38309]

ANPCyT Agencia Nacional de Promocion Cientifica y Tecnologica (Argentina)[01152]

Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT)

Agencia Nacional de Promoción Científica y Tecnológica (ANPCyT)

ANPCyT Agencia Nacional de Promocion Cientifica y Tecnologica (Argentina)[02288]

CONICET (Argentina)[6559]

Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina (CONICET)

Latin-American Centre for Physics (CLAF)

Latin-American Centre for Physics (CLAF)