Oxygen ion dynamics in pyrochlore-type ionic conductors: Effects of structure and ion–ion cooperativity

AbstractWe analyze in this work the influence of ordering on the oxygen ion dynamics in the ionic conductor Gd2(Ti0.65Zr0.35)2O7, prepared by mechanical milling. As-prepared powder phase presents a metastable anion deficient fluorite-type of structure below 800°C becoming a disordered pyrochlore above this temperature. Such phase transformation implies a significant increase in the ionic conductivity of this material as a result of a systematic decrease in the activation energy for the dc conductivity, from 1.23 to 0.78 eV. Electrical conductivity relaxation is well described by the Kohlrausch-Williams-Watts (KWW) stretched exponential function with the fractional exponent n decreasing systematically with increasing sintering temperature (increasing ordering) as a result of decreasing ion-ion interactions in better ordered samples.

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Oxygen ion dynamics in yttria-stabilized zirconia as evaluated by solid-state 17O NMR spectroscopy

Solid State Ionics ◽

10.1016/j.ssi.2006.07.040 ◽

2006 ◽

Vol 177 (35-36) ◽

pp. 3063-3068 ◽

Cited By ~ 14

Author(s):

T VIEFHAUS ◽

T BOLSE ◽

K MULLER

Keyword(s):

Solid State ◽

Nmr Spectroscopy ◽

Yttria Stabilized Zirconia ◽

Ion Dynamics ◽

Stabilized Zirconia ◽

17O Nmr ◽

Oxygen Ion ◽

17O Nmr Spectroscopy

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Oxygen Ion Dynamics in the Earth's Ring Current: Van Allen Probes Observations

Journal of Geophysical Research Space Physics ◽

10.1029/2019ja026801 ◽

2019 ◽

Vol 124 (10) ◽

pp. 7786-7798 ◽

Cited By ~ 5

Author(s):

Chao Yue ◽

Jacob Bortnik ◽

Wen Li ◽

Qianli Ma ◽

Chih‐Ping Wang ◽

...

Keyword(s):

Ring Current ◽

Ion Dynamics ◽

Oxygen Ion ◽

Van Allen Probes

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Diffusion in Nanocrystalline Ion Conductors Studied by Solid State NMR and Impedance Spectroscopy

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.283-286.705 ◽

2009 ◽

Vol 283-286 ◽

pp. 705-715 ◽

Cited By ~ 12

Author(s):

Paul Heitjans ◽

Martin Wilkening

Keyword(s):

Dynamic Properties ◽

Average Particle Size ◽

High Energy ◽

Average Particle ◽

Ion Dynamics ◽

Ionic Conductors ◽

Present Contribution ◽

Energy Ball ◽

Phase Systems ◽

Ion Conductors

Materials with an average particle size of less than about 50 nm often show new or at least enhanced physical properties. In many cases nanocrystalline ionic conductors exhibit a high increase of cation, e. g. Li+, or anion, e. g. F−, diffusivity. In the present contribution we review recent studies on ion dynamics in nanocrystalline ion conductors, both single-phase systems and composites, being prepared by high-energy ball milling. These include, e.g., LiTaO3, Li2O:Al2O3, LiF:Al2O3, BaF2, CaF2, BaF2:CaF2 and (BaF2:CaF2):Al2O3. Dynamic properties were probed by 7Li and/or 19F NMR line shape and relaxation as well as ion conductivity measurements.

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