Ceramics, squared: J. Carlos Diez and colleagues discuss thermoelectric ceramics and the challenge of optimizing their properties

Abstract

The introduction of intermetallic semiconductor materials, with higher thermoelectric performances than their metallic counterparts, has resulted in their practical application in thermo-electric modules. These modules can be found as Peltier devices, when used for refrigeration purposes, or Seebeck devices when used for electrical energy generation. Current applications of this kind of material include the environmentally friendly recovery of industrial and automobile waste heat, and in the production of electrical energy in radioisotope thermoelectric generators installed on spacecrafts, or in lighthouses located in isolated regions. At the Department of Materials Science, Universidad de Zaragoza (Spain) much effort has been devoted to optimizing material properties by texturing using the laser floating zone (LFZ) technique. The group is pioneering the application of the LFZ technique on cobaltites to enhance grain orientation and, consequently, thermoelectric properties.