摘要

Nanocrystalline ZrO2-CeO2 (ZC) solid solution is synthesized by high energy ball-milling the powder mixture of monoclinic (m) ZrO2-10 mol% CeO2 in air medium. X-ray powder diffraction (XRD) patterns show that the method IS effective to synthesize cubic (c) ZrO2 phase within a short milling time. Formation mechanism, structural and microstructural changes of different phases and relative phase abundances have been estimated by Rietveld analysis of XRD patterns. The dc conductivity has been enhanced due to monoclinic to cubic phase transformation. A transformation from small polaron hopping to correlated barrier hoping has been observed from the of temperature dependence frequency exponent study. A crossover from negative to positive ac magnetoconductance has been observed at temperature T = 280 K and 230 K for unmilled (ZC0H) and 8 h (ZC8H) milled samples, respectively.

  • 出版日期2013-10

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