X-ray absorption fine structure (XAFS) measurements near the Zr K-edge for pure ZrO2 and stabilized cubic ZrO2 (+8% Y 2O3) were performed under pressure up to 7.8 GPa using a multi-anvil high-pressure device and synchrotron radiation at BL14B1, SPring-8, Hyogo. The edge feature of XANES spectra for stabilized ZrO2 with defect-fluorite type structure looks like an addition of both shapes for the P21/c and Pbca phases in pure ZrO2. The pressure dependence of Zr-O distances is almost similar in the pure and stabilized ZrO2. The contribution of the thermal vibration can be extracted from σ2 by temperature-dependent EXAFS experiments. The contribution of static disorder is extremely large compared with other super ionic conductors. The potential coefficient a for an effective pair potential, V(u) = au 2/2, has been evaluated from the experimental σ2 and is 8.44(6) eV Å-2. Local structure and compression effect for stabilized cubic ZrO2 especially looks like those in the Pbca phase of pure ZrO2.
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