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 ScO1.5 doping. The crystal structures of monoclinic, tetragonal, cubic, and rhombohedral (Sc2Zr7O17, s-phase) solid-solution phases have been refined by using the Rietveld analysis of the XRD data at room temperature of arc-melted ZrO2-XScO1.5 (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 ScO1.5 doping. Raman scattering, as well as XRD, was useful to investigate the phase assemblage. Moreover, we could obtain Raman spectra of the s-phase probably for the first time.

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