A high temperature study on thermodynamic, thermal expansion and electrical properties of BaCe0.4Zr0.4Y0.2O3−δ proton conductor

BaCe0.4Zr0.4Y0.2O3−δ (BCZY) was synthesized by solid state reaction, calcined and sintered at 1600 °C for 12 h. Crystal structure was studied by X-ray diffraction (XRD). Morphology and porosity were determined by scanning electron microscopy (SEM). Crystalline structure, oxygen non-stoichiometry, li...

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Detalles Bibliográficos
Autores: Basbus, Juan Felipe, Arce, Mauricio Damián, Prado, Fernando Daniel, Caneiro, Alberto, Mogni, Liliana Verónica
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/50069
Acceso en línea:http://hdl.handle.net/11336/50069
Access Level:acceso abierto
Palabra clave:Bace0.4zr0.4y0.2o3&Minus;Δ Electrolyte
Bulk Conductivity
Grain Boundary Conductivity
Isotopic Effect
Pc-Sofc
Proton Incorporation
https://purl.org/becyt/ford/2.5
https://purl.org/becyt/ford/2
Descripción
Sumario:BaCe0.4Zr0.4Y0.2O3−δ (BCZY) was synthesized by solid state reaction, calcined and sintered at 1600 °C for 12 h. Crystal structure was studied by X-ray diffraction (XRD). Morphology and porosity were determined by scanning electron microscopy (SEM). Crystalline structure, oxygen non-stoichiometry, linear expansion and electrical conductivity were characterized under oxidizing and reducing atmosphere by high temperature X-ray diffraction (HT-XRD), thermogravimetry (TG), dilatometry, and electrochemical impedance spectroscopy (EIS), respectively. Chemical stability under CO2-rich atmosphere was evaluated by TG. BCZY electrical conductivity was studied by EIS under O2-containing atmosphere with water vapor (2% H2O) and heavy water vapor (2% D2O) in order to evaluate protonic conductivity. Throughout these techniques, interstitial proton incorporation/loss was observed under oxidizing and reducing atmosphere, between 300 and 500 °C. The conductivity presents two contributions. The bulk conductivity at high frequencies takes the same value regardless wet oxidizing or reducing atmosphere, decreasing its value in presence of D2O vapor supporting H-conductivity. On the other hand, the grain boundary conductivity was strongly dependent on the nature of wet atmosphere.