OXIDE CERAMICS AS THERMOELECTRIC MATERIALS

Abstract

Nowadays, there is a renewed interest about thermoelectric materials research, it is driven by both the new possibilities of design and growth that current the materials science offers and by the need of finding materials that allow us to build efficient solid-state coolers and power generators. The performance of a thermoelectric material is a function of its figure of merit ( (ZT= S2T / pK, where S is the Seebeck coeffi cient, p the electrical resistivity and K the thermal conductivity). The goal of thermoelectric materials research is to find high-ZT compounds. In this sense, sorne ofthese research efforts are focused on minimizing lattice thermal conductivity, while other are focused on increasing the thermoelectric power factor (PF = S2/p). In this work, an overview oftlrermoelectric properties of YBa2Cu307_0 (YBCO), Lar,.Sr,.Cu04+0 (LSCO) and La,_xSr,.Co03 (LSCoO) is presented. The best values obtained for power factor (PF=J8µWIK2cm) and figure of merit (ZT=0,5) are comparable to those of conventional semiconductors, which are current used in thermoelectric devices. These results allow us consider these compounds as promissory thermoelectric materials, which could work at room temperature and below it.