Laboratory of Oxide Materials

Thermoelectric materials

Thermoelectric cobaltites

Grant Agency of the Czech Republic (2009-2011).
Collaboration with Institute of Chemical Technology, Prague.

The project deals with a fundamental research on novel oxide thermoelectric materials of p-type considered for the electric power generation using waste heat. As concerns the conversion efficiency of such thermoelectric generators, the materials should operate in wide temperature range and keep at the same time a high figure of merit, ZT =(S²R)T, where S is the Seebeck coefficient, R is the ratio of electric resistivity and thermal conductivity and T is the actual temperature of the thermoelectric segment. In this respect, some cobalt oxides have been found promising, especially thanks to the pioneering work of Terasaki on thermoelectric properties of Na_0.6CoO₂ in 1997. The present project is focused on material research of a broad class of complex cobaltites, based both on the hexagonal and tetragonal arrangements of the thermoelectrically active CoO₂ layers. The properties of the cobaltites will be optimized by an improvement of their intrinsic properties through modification of the chemical composition, as well as by a control of morphology and microstructure of the prepared materials.

Energy conversion by thermoelectric effect: from theory to applications

The objective of this course is to present the basics of energy conversion by thermoelectric effects. Starting from thermal conduction, electrical resistivity and the origin of thermoelectric power in solids, we will see that the coupling between these properties, in a certain category of materials, gives rise to effects that can be exploited advantageously to cool the body or generate electricity.