ABSTRACT
In this chapter recent results of the thermoelectric properties of bismuth telluride and its solid solutions
are presented. Many authors have previously studied these materials,
which possess the characteristics
of a good thermoelectric material at room temperature. However, these studies are relatively old and the
results are, in general, dispersed throughout the literature. In most of the samples investigated, it is
difficult to relate the thermoelectric properties to the basic state of the material. The effects of doping are
masked by the intrinsic properties, or excess of one of the components, with the starting material often
thermo dynamically poorly defined. The study of Satterthwaite and Ure,
and Brebrick
on bismuth
telluride revealed a domain of existence limited by a solidus line at high temperatures. The resulting
deviation from stoichiometry can be expressed in terms of native defects, which are electrically active and
related to the thermoelectric properties.