Effect of the synthesis conditions on the properties of La0.15Sm0.35Sr0.08Ba0.42FeO3 − δ cathode material for SOFCs
The perovskite La0.15Sm0.35Sr0.08Ba0.42FeO3 − δ has been prepared by the glycine nitrate (GNC) route, varying the fuel/oxidizer ratio (glycine/nitrate, G/N = 1 and 2) and cooling rate (slow cooling and air-quenched), in order to study the influence of sample preparation on the materials' proper...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2017 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/181920 |
| Acceso en línea: | http://hdl.handle.net/10261/181920 |
| Access Level: | acceso abierto |
| Palabra clave: | Chemical synthesis Oxygen content SOFC Cathode material Impedance spectroscopy |
| Sumario: | The perovskite La0.15Sm0.35Sr0.08Ba0.42FeO3 − δ has been prepared by the glycine nitrate (GNC) route, varying the fuel/oxidizer ratio (glycine/nitrate, G/N = 1 and 2) and cooling rate (slow cooling and air-quenched), in order to study the influence of sample preparation on the materials' properties, in the context of their application as a cathode material for SOFCs. For this, the performance of the prepared mixed ion and electron conducting perovskite oxides is dictated by their structure, oxygen stoichiometry (3 − δ), chemical composition and thermal expansion properties. High-resolution Synchrotron X-ray powder diffraction patterns were collected at room temperature and at 700 and 800 °C. It was found that the materials had a cubic crystal structure at these temperatures. As expected, 3 − δ decreased as temperature increased, and was slightly smaller for the quenched sample. Higher electrical conductivity values were obtained for the sample with G/N = 1 (air-quenched) in the cooling rate. At 700 and 800 °C the cathode synthesized with G/N = 1 and air-quenched showed the smallest polarization resistance values in impedance spectroscopy studies. Therefore, the physicochemical and electrochemical characterization clearly demonstrated the influence of the synthetic conditions on the cathode performance. |
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