Paper number 283

BISMUTH-BASED THERMOELECTRIC NANOCOMPOSITES

F. Brochin, X. Devaux, B. Lenoir, R. Martin-Lopez, H. Scherrer

Laboratoire de Physique des Matériaux, UMR CNRS 7556, Ecole des Mines
54 042 Nancy Cedex, France

Summary

Bulk bismuth-silica nanocomposites have been prepared via powder metallurgy to study the influence of silica inclusions on the transport properties of Bi-based materials. Bi-SiO2 ultrafine powders were produced by an arc-plasma processing. TEM investigations revealed the presence of a nanometric silica shell around each Bi grain. The nanocomposite powders were cold pressed and sintered close to the melting temperature of bismuth. The electrical resistivity, the thermoelectric power, the thermal conductivity and the thermoelectric figure of merit were measured from 65 K to 300 K. The transport properties of pure single crystalline and polycrystalline bismuth are compared to those of nanocomposite materials.

Keywords

nanocomposites, bismuth, silica, thermoelectricity, transport properties.