Enhancement of mechanical and thermoelectric properties of Ca3Co4O9 by Ag addition

Ca3Co4O9 + x wt.% Ag (x = 0, 1, 3, 5, and 10) polycrystalline thermoelectric ceramics have been prepared by a sol–gel route via nitrates followed by high temperature treatment before sintering. Out-of-plane XRD data have shown that major phase is the Ca3Co4O9 one, accompanied by metallic Ag. SEM obs...

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Detalles Bibliográficos
Autores: Kahraman, F., Madre, M. A., Rasekh, Sh., Salvador, C., Bosque, P., Torres, M. A., Diez, J. C., Sotelo, Andres
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:2015
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/147688
Acceso en línea:http://hdl.handle.net/10261/147688
Access Level:acceso abierto
Palabra clave:Thermoelectricity
Flexural strength
Ca3Co4O9
Descripción
Sumario:Ca3Co4O9 + x wt.% Ag (x = 0, 1, 3, 5, and 10) polycrystalline thermoelectric ceramics have been prepared by a sol–gel route via nitrates followed by high temperature treatment before sintering. Out-of-plane XRD data have shown that major phase is the Ca3Co4O9 one, accompanied by metallic Ag. SEM observations have agreed with the XRD data. Apparent density measurements have revealed that all samples possess densities ranging between 80% and 90% when Ag content is raised. Mechanical properties have shown a drastic increase of bending stress when Ag is added to the samples. Electrical resistivity decreases with the Ag content, compared with the pure ones, while Seebeck coefficient slightly decreases. Maximum power factor values around 0.43 mW/K2 m at 800 °C have been achieved for the 10 wt.% Ag samples which is much higher than the measured in the pure Ca3Co4O9 samples.