Thermoelectric cobaltites (THERMCO)

Abstract

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 Na0.6CoO2 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.