1. High-temperature electrical transport behaviors in textured Ca3Co4O9-based polycrystalline ceramics.
- Author
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Yuan-Hua Lin, Jinle Lan, Zhijian Shen, Yuheng Liu, Ce-Wen Nan, and Jing-Feng Li
- Subjects
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POLYCRYSTALLINE semiconductors , *CERAMICS , *SINTERING , *FORGING research , *ELECTRICAL resistivity , *THERMOELECTRICITY , *HEAT resistant materials - Abstract
Highly (00l) oriented Ca3Co4O9-based ceramics were fabricated by spark plasma sintering combined with a dynamic forging process. The grain orientation is effective in lowering the electrical resistivity and enhancing the thermoelectric power factor but with little influence on the Seebeck coefficient. A metallic-to-semiconducting transition temperature can be observed and the activation energy is almost independent of the La-doping. All of the Ca3Co4O9-based ceramic samples exhibit large thermoelectric power, and the figure of merit for La-doped Ca3Co4O9 sample can reach 0.26 at 975 K, which can be a promising candidate of p-type material for high-temperature thermoelectric application. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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