Evaluation of layered TiS2-based thermoelectric elements fabricated by a centrifugal heating technique

Abstract

We have developed a centrifugal heating apparatus to fabricate layered TiS2-based thermoelectric elements, and evaluated their thermoelectric properties.We found that layered (SnS)1.2(TiS2) 2 bulk elements with preferred crystallographic orientation can be produced within a quartz tube under a centrifugal acceleration of 1,000 g or higher and at a maximum temperature of 1,073K or higher. With the increasing centrifugal acceleration from 1,000 to 8,000 g, the electrical conductivity of the produced specimen was almost doubled possibly because of the increased degree of crystal-axis orientation. For the specimens produced at 8,000 g, we estimated a maximum thermoelectric figure of merit, ZT, of approximately 0.2 (673 K). We have thus demonstrated that it is possible to use the centrifugal heating technique to fabricate layered TiS2-based thermoelectric elements directly from the powdered raw materials. © 2011 The Ceramic Society of Japan.