Thermoelectric properties of (Bi,Sb)/sub 2/Te/sub 3/ solid solution with P-type conductivity

Presented are the study results of the thermoelectric properties of solid solutions with P-type conductivity (Bi,Sb)/sub 2/Te/sub 3/ that have been grown by method of zone melting. The most figure of merit was observed in the solid solutions of such chemical composition where tellurium solubility does not depend on the temperature of melting. For compositions (Bi/sub 0.2/Sb/sub 0.8/)/sub 2/Te/sub 3/ the area of composition where figure of merit reaches its peak, corresponds to the transition of regular tellurium solubility into retrograde solubility. Such solid solutions are characterised by the shortest periods of crystal lattice. It has been shown that among solid solutions (Bi/sub 1-x/Sb/sub x/)/sub 2/Te/sub 3/+y for x=0.5-0.8, there are no bad ones in terms of thermoelectric efficacy. For any meaning of x within the range of 0.5-0.8 there is a meaning y and the temperature when the maximum on the temperature dependence curve of thermoelectric efficacy reaches its peak. Figure of merit peak is shifting to the low temperatures zone (180 K) when x gets closer to 0.5 and reaches the value of 3.6-3.8 10/sup -3/ K/sup -1/ and the meaning of specific electric conductivity that corresponds to figure of merit, is close to 1400 Ohm/sup -1/ cm/sup -1/.