Synthesis and thermoelectric properties of p-type $Ba_{8}Au_{x}Si_{46-x}$clathrate

Content Provider	Scilit
Author	Saisho, Makoto Bin, Liu Nagatomo, Yuya Nakakohara, Yusuke Teranishi, Ryo Munetoh, Shinji
Copyright Year	2012
Description	Journal: Journal of Physics: Conference Series Poly-crystalline $Ba_{8}Au_{x}Si_{46−x}$ clathrates were synthesized by the arc melting method and a subsequent annealing treatment. The as-synthesized sample contained some precipitates rich in Au at the grain boundaries, and the precipitates were reduced by annealing at 1000 °C. The Au content of the clathrate phase for the as-synthesized sample, $Ba_{7.4}Au_{4.7}Si_{41.3}$, was slightly lower than that for the stoichiometric composition, $Ba_{8}Au_{6}Si_{40}$. In the annealed samples, the Au content of the clathrate phase increased with annealing time. These results indicated that Au can diffuse from Au-rich precipitates to the clathrate phase by annealing. The Seebeck coefficient of the as-synthesized and 1 hour annealed sample, $Ba_{7.5}Au_{5.7}Si_{40.3}$, were -80 and +100 μV/K at 500 °C, respectively. This suggested that the carrier type was changed by the Au content in the clathrate. In the samples annealed for longer than 1 hour, the Seebeck coefficient decreased with annealing time. This indicated that the hole carrier concentration increased in excess because of overdoping due to the diffusion of Au.
Related Links	http://iopscience.iop.org/article/10.1088/1742-6596/379/1/012009/pdf
ISSN	17426588
e-ISSN	17426596
DOI	10.1088/1742-6596/379/1/012009
Journal	Journal of Physics: Conference Series
Issue Number	1
Volume Number	379
Language	English
Publisher	IOP Publishing
Publisher Date	2012-08-07
Access Restriction	Open
Subject Keyword	Journal: Journal of Physics: Conference Series Business and Management Grain Boundary
Content Type	Text
Resource Type	Article
Subject	Physics and Astronomy