Structural changes of scandia-doped zirconia solid solutions: Rietveld analysis and Raman scattering

Powder X-ray diffractometry (XRD) and Raman scattering measurements were used to study the structural changes of compositionally homogeneous metastable ZrO₂ solid solutions induced by ScO_1.5 doping. The crystal structures of monoclinic, tetragonal, cubic, and rhombohedral (Sc₂Zr₇O₁₇, β-phase) solid-solution phases have been refined by using the Rietveld analysis of the XRD data at room temperature of arc-melted ZrO₂-XScO_1.5 (X = 0, 2, . . . , 20, and 22 mol%) samples. The results can be interpreted as indicating that the structures of the monoclinic and tetragonal phases approach those of the tetragonal and cubic phases, respectively, by ScO_1.5 doping. Raman scattering, as well as XRD, was useful to investigate the phase assemblage. Moreover, we could obtain Raman spectra of the β-phase probably for the first time.