Thermoelectricfigure of merit of M-sulphides (M = Fe, Pd, Ti...) thin films

A.Pascual¹, J.R. Ares², I.J. Ferrer¹, C.R.Sánchez¹

¹Dpto. de Física de Materiales, C-IV, UniversidadAutónoma de Madrid, Cantoblanco, 28049-Madrid, España

²Laboratoire de Chimie Metallurgique des Terres Rares,ISCA-CNRS, Rue Henri Dunant 2-8, 94320 Cedex, France

Interest on thethermoelectric materials is increasing due to the strong demand of clean energysources. Furthermore, the optoelectronic communication market contributes tothis increasing demand requiring small size power supplies. In this sense, thinfilm thermoelectric materials are a good alternative versus bulk materials. Wehave grown transition metal (Fe, Co, Pd, Ti...) sulphide thin films (doped andnon-doped) and we have measured the electrical and transport properties duringthe formation of the films. We have performed preliminary measurements on thesethin films to determine the thermoelectric figure of merit, ZT, using theHarman method¹. By applying this method, it is not necessary to knowthe thermal conductivity of the film to determine ZT. The thermoelectric figureof merit of non-doped FeS₂, CoS₂, PdS and TiS₂films was measured at different temperatures. Values of ZT were found to below, but it is expected to get higher ZT values by controlling the filmdeposition parameters and doping them. The films were characterised using XRDto identify their crystalline phases. The thermoelectric figure of merit valueswill be reported and discussed.

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