High Temperature Crystal Chemistry and Oxygen Permeation Properties of the Mixed Ionic–Electronic Conductors LnBaCo2O5 + δ ( Ln = Lanthanide )
The high temperature crystal chemistry and oxygen permeation properties of the cation-ordered LnBaCo2 O5+δ perovskite oxides [lanthanide (Ln)=Pr, Nd, and Sm] have been investigated in comparison with the cation-disordered La0.5 Ba0.5 CoO3-δ perovskite. The LnBaCo2 O5+δ (Ln=Pr, Nd, and Sm) oxides exh...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2009 |
| País: | Argentina |
| Institución: | Consejo Nacional de Investigaciones Científicas y Técnicas |
| Repositorio: | CONICET Digital (CONICET) |
| Idioma: | inglés |
| OAI Identifier: | oai:ri.conicet.gov.ar:11336/69979 |
| Acceso en línea: | http://hdl.handle.net/11336/69979 |
| Access Level: | acceso abierto |
| Palabra clave: | Catodo de Sofc Óxidos Conductores Mixtos Cobaltitas Permeabilidad e Oxígeno https://purl.org/becyt/ford/1.4 https://purl.org/becyt/ford/1 |
| Sumario: | The high temperature crystal chemistry and oxygen permeation properties of the cation-ordered LnBaCo2 O5+δ perovskite oxides [lanthanide (Ln)=Pr, Nd, and Sm] have been investigated in comparison with the cation-disordered La0.5 Ba0.5 CoO3-δ perovskite. The LnBaCo2 O5+δ (Ln=Pr, Nd, and Sm) oxides exhibit a metal-insulator transition at T<200°C, as evidenced by total conductivity measurements and high temperature X-ray diffraction data and an oxygen vacancy order-disorder transition at T >350°C in air, as evidenced by an orthorhombic to tetragonal transition. At a given temperature, the oxygen permeation flux decreases from Ln=La to Nd to Sm due to the changes in crystal symmetry and lattice strain. The oxygen permeation mechanism in the Ln=Nd is bulk-diffusion-limited rather than surface-exchange-limited for membrane thickness L1≥1 mm. |
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