EFFECT OF FEATURES IN GRAIN STRUCTURE ON THE THERMOELECTRIC PROPERTIES OF COMPOUNDS BASED ON BISMUTH TELLURIDE

Abstract

Specific mechanisms of grain structure effect on the thermoelectric properties (specific electrical resistivity and total thermal conductivity) of the Bi1.9Gd0.1Te3 compound have been analyzed. These mechanisms are as follows: 1) forming the surface Te vacancies at grain boundaries acting as donor centres; 2) changing the elemental composition of the grains at high-temperature Te evaporation under thermal treatment of material to prepare the samples with desired average grain size.