In situ synthesis and thermoelectric properties of Te/FeTe2 composites

Besides excellent thermoelectric performance in the medium temperature region, the elemental semiconductor Tellurium (Te) has the character of simple composition and not easy to segregate, which also makes it very advantageous in practical manufacturing and application, and has attracted extensive attention in recent years. However, the carrier concentration of intrinsic Te is too low to obtain high thermoelectric performance. Only high toxic As doing is effective to optimize the electrical transport properties. In this study, we used the in situ compositing method to overcome the disadvantage of poor electrical transport properties of Te. The results show that simple mixing followed by high-pressure sintering method can form dispersoid distribution of FeTe2 in the matrix of Te. High carrier concentration of 2.6 to 4.8 x 10(19) cm(-3) was obtained for the Te/FeTe2 composites, which results in an enhanced power factor. Simultaneously, the phonon scattering of the second phase of FeTe2 reduces the phonon thermal conductivity of Te. This study shows that FeTe2 composition helps to overcome the disadvantage of poor electrical transport properties of elemental semiconductor Te.