Reduction in Processing Time in Ca(3)Co(4)O(9+δ) Ceramics through Nanoprecursors Produced by an Easily Scalable and Environmentally Friendly Process

Attrition milling is an easily scalable and environmentally friendly process used to produce Ca(3)Co(4)O(9+δ) nanoprecursors in a relatively short time. Sintered materials produced through the classical solid-state method, involving ball milling, show much larger grain sizes and slightly lower density than those obtained in samples produced from attrition-milled precursors. On the other hand, electrical resistivity has been drastically decreased, accompanied with a slight decrease in the Seebeck coefficient in samples obtained from these attrition-milled precursors. Moreover, the use of an attrition milling process leads to a very important reduction in processing time (around 75%), together with a slight power factor improvement of around 10%, when compared to the classically prepared samples.