TY - JOUR
T1 - Temperature dependence of effective grain core/single crystal dielectric constants for acceptor-doped oxygen ion conductors
AU - Perry, Nicola H.
AU - Yeh, Ted C.
AU - Mason, Thomas O.
PY - 2011/2/1
Y1 - 2011/2/1
N2 - Effective grain core or single crystal dielectric constants of four solid oxide electrolytes-yttria-stabilized zirconia (YSZ with 8 and 7 mol% yttria), tetragonal zirconia polycrystals (TZP with 3 mol% yttria), strontium- and magnesium-doped lanthanum gallate (LSGM), and gadolinia-doped ceria (GDC, with 20 mol% gadolinia)-were studied as a function of temperature by AC-impedance spectroscopy and equivalent circuit fitting. Unlike their undoped counterparts, the acceptor-doped oxides consistently exhibited an upturn in effective grain core/single crystal dielectric constant in the vicinity of 350-500 K. This temperature-dependent behavior was attributed to the onset of thermally activated dipolar relaxation-an explanation supported by the appearance of loss tangent peaks at higher temperatures. Differences between "effective" dielectric constants and frequency-dependent complex dielectric constants for the grain core/single crystal frequency range, and applications of the effective dielectric constant data are discussed.
AB - Effective grain core or single crystal dielectric constants of four solid oxide electrolytes-yttria-stabilized zirconia (YSZ with 8 and 7 mol% yttria), tetragonal zirconia polycrystals (TZP with 3 mol% yttria), strontium- and magnesium-doped lanthanum gallate (LSGM), and gadolinia-doped ceria (GDC, with 20 mol% gadolinia)-were studied as a function of temperature by AC-impedance spectroscopy and equivalent circuit fitting. Unlike their undoped counterparts, the acceptor-doped oxides consistently exhibited an upturn in effective grain core/single crystal dielectric constant in the vicinity of 350-500 K. This temperature-dependent behavior was attributed to the onset of thermally activated dipolar relaxation-an explanation supported by the appearance of loss tangent peaks at higher temperatures. Differences between "effective" dielectric constants and frequency-dependent complex dielectric constants for the grain core/single crystal frequency range, and applications of the effective dielectric constant data are discussed.
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U2 - 10.1111/j.1551-2916.2010.04093.x
DO - 10.1111/j.1551-2916.2010.04093.x
M3 - Article
AN - SCOPUS:79751478742
VL - 94
SP - 508
EP - 515
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
SN - 0002-7820
IS - 2
ER -