Thermoelectric properties of /spl beta/-FeSi/sub 2/ with oxide-particles doping

Author

Suzuki, H. ; Mochizuki, S. ; Sugihara, S. ; Shiraishi, K. ; Kajikawa, T.

Author_Institution

Dept. of Mater. Sci. & Ceramic Technol., Shonan Inst. of Technol., Fujisawa, Japan

fYear

1999

fDate

Aug. 29 1999-Sept. 2 1999

Firstpage

146

Lastpage

149

Abstract

We investigated thermoelectric properties of Fe-Si systems (/spl alpha/, /spl epsiv/ and /spl beta/-phase) with oxide particles diffused in. The oxides used here were La/sub 2/O/sub 3/, Yb/sub 2/O/sub 3/, Ag/sub 2/O, NiO and Cr/sub 2/O/sub 3/. They were sintered by solid reaction method, then they were annealed for 3 hours. We found that the shorter annealing time was obtained by adding a small amount of oxides, lattice thermal conductivity decreased by addition of Yb/sub 2/O/sub 3/. Interfacial effects were found that carriers moved between the solidified Ag and the Fe-Si systems by addition of Ag/sub 2/O, and the barrier between the oxides and the Fe-Si systems was observed by addition of La/sub 2/O/sub 3/ and Yb/sub 2/O/sub 3/. Figure of merit was the following in Fe/sub 0.92/Mn/sub 0.08/Si/sub 2/ after 3 hours annealing; Z=1.85/spl times/10/sup -4/ (K/sup -1/) for 3 wt% Yb/sub 2/O/sub 3/, Z=0.75/spl times/10 /sup 4/(K/sup -1/) for 3, 5 and 10 wt% Ag/sub 2/O and the unadded.

Keywords

Seebeck effect; annealing; crystal microstructure; iron compounds; semiconductor doping; semiconductor materials; thermal conductivity; thermoelectricity; /spl beta/-FeSi/sub 2/; 3 hour; Ag/sub 2/O; Cr/sub 2/O/sub 3/; FeSi/sub 2/; La/sub 2/O/sub 3/; NiO; Yb/sub 2/O/sub 3/; annealing time; figure of merit; interfacial effects; lattice thermal conductivity; oxide-particles doping; sintering; solid reaction method; thermoelectric properties; Annealing; Ceramics; Doping; Grain boundaries; Grain size; Lattices; Materials science and technology; Temperature measurement; Thermal conductivity; Thermoelectricity;

fLanguage

English

Publisher

ieee

Conference_Titel

Thermoelectrics, 1999. Eighteenth International Conference on

Conference_Location

Baltimore, MD, USA

ISSN

1094-2734

Print_ISBN

0-7803-5451-6

Type

conf

DOI

10.1109/ICT.1999.843354

Filename

843354