Thermoelectric properties of p-type (Bi₂Te₃)_x(Sb₂Te₃)_1-x prepared via bulk mechanical alloying and hot pressing

In the present paper, starting from elemental Bi, Sb and Te granules with 5 N purity and 1-5 mm diameter, p-type single phase (Bi₂Te₃)_x(Sb₂Te₃)_1-x (x=0.20, 0.225, 0.25, 0.275 and 0.30) thermoelectric materials with high densification (>99% theoretical density) were prepared via bulk mechanical alloying (BMA) and hot pressing (HP). Their thermoelectric properties, are less composition sensitive in the composition range of x≤0.25 and are comparable to that of those materials prepared by travelling heater method (THM); the figures of merit of (Bi₂Te₃)_x(Sb₂Te₃)_1-x are about 3×10^-3/K. When x>0.25, the figures of merit of (Bi₂Te₃)_x(Sb₂Te₃)_1-x decreased rapidly with increasing x.