Granular and Lamellar Thermoelectric Oxides Consolidated by Spark Plasma Sintering
Résumé
Using the spark plasma sintering (SPS) technique, dense nanostructured Ca0.95Sm0.05MnO3 (n-type) and textured Ca3Co4O9 (p-type) ceramics were prepared. Nanoceramic powders of doped n-type were synthesized using two routes: coprecipitation and solid-state reaction. The SPS method has been used to control the samples’ densification and grain growth. Microstructural investigations reveal that the SPS technique results in high bulk density and homogeneous morphology for Ca0.95Sm0.05MnO3, and grain alignment for Ca3Co4O9. The thermoelectric and mechanical properties were investigated, showing a dependence on the starting grain size and being governed by the SPS conditions.