Conductivity of R1 − yPbyF3 – y (R = Pr, Nd) Solid Electrolytes with the Tysonite Structure

N. I. Sorokin N. I. Sorokin , D. N. Karimov D. N. Karimov , I. I. Buchinskaya I. I. Buchinskaya
Russian Journal of Electrochemistry
Abstract / Full Text

The dependence of the ionic conductivity σdc(y) of crystallization products on the concentration is studied by impedance spectroscopy in quasi-binary systems RF3−PbF2 (R = Pr, Nd) in the region of compositions R1 − yPbyF3 – y (0 ≤ y ≤ 0.22) enriched with the rare-earth component RF3. The single-phase tysonite (space group \(P\bar {3}c1\)) solid solutions R1 − yPbyF3 – y are synthesized from the melt by directional crystallization for y < 0.1. The maximum conductivity σdc at 296 ± 1 К is found to be 7 × 10−5 and 3 × 10−5 S/cm for crystals with the composition Pr0.96Pb0.04F2.96 and Nd0.95Pb0.05F2.95, respectively. For 9−10 mol % PbF2, the samples become two-phase, the second phase—the fluorite solid solution Pb1 − xRxF2 + x—appears, and their ionic conductivity decreases.

Author information
  • Shubnikov Institute of Crystallography, Federal Scientific Research Center “Crystallograpy and Photonics,” Russian Academy of Sciences, Moscow, Russia

    N. I. Sorokin, D. N. Karimov & I. I. Buchinskaya

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