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Título:
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Synthesis and electrical properties of the pyrochlore-type Gd_(2-y)La_(y)Zr_(2)O_(7) solid solution
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Autores:
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Díaz Guillén, J. A. ;
Díaz Guillén, M. R. ;
Padmasree, K. P. ;
Almanza, J. M. ;
Fuentes, A. F. ;
Santamaría Sánchez-Barriga, Jacobo ;
León Yebra, Carlos
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Tipo de documento:
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texto impreso
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Editorial:
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Sociedad Española de Cerámica y Vidrio, 2008-05
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Dimensiones:
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application/pdf
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Nota general:
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info:eu-repo/semantics/restrictedAccess
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Idiomas:
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Palabras clave:
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Estado = Publicado
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Materia = Ciencias: Física: Electricidad
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Materia = Ciencias: Física: Electrónica
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Tipo = Artículo
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Resumen:
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Different compositions in the pyrochlore-type Gd_(2-y)La_(y)Zr_(2)O_(7) solid solution (0 ? y ? 1) were prepared at room-temperature by mechanically milling stoichiometric mixtures of the corresponding oxides. Irrespective of their lanthanum content, as-prepared powder samples consist of single-phase anion deficient fluorite materials, although long-range ordering of cations and anion vacancies characteristic of pyrochlores was observed in all cases after firing the samples at 1500°C. Interestingly, activation energy for oxygen migration in the series decreases as La-content increases, from 1.13 eV for Gd_(2)Zr_(2)O_(7) to 0.81 eV for GdLaZr_(2)O_(7), whereas ionic conductivity was found to be almost La-content independent, at least for y ? 0.8 at T = 500°C and y ? 0.4 at T = 800°C. These results are explained in terms of weaker ion-ion interactions in better ordered structures (i.e., as La-content increases) and highlight the importance of structural ordering/disordering in determining the dynamics of mobile oxygen ions.
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En línea:
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https://eprints.ucm.es/id/eprint/30495/1/LeonC147.pdf
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