Thermoelectric properties of the doped Kondo insulator: NdxCe3-xPt3Sb4

The temperature dependence of the thermopower, electrical resistivity, and thermal conductivity were explored for the solid solution NdxCe3-xPt3Sb4 ob tained from the parent Kondo insulator Ce3Pt3Sb4. While Ce3Pt3Sb4 is a semi conductor with a small activation energy (E-a approximate to 0.05+/-0.01 eV ) and a relatively large thermopower (S=112+/-4 mu V/K at 300 K), Nd3Pt3Sb4 is a simple metal with a typically low thermopower (S= 8 +/- 1 mu V/K at 3 00 K). The thermoelectric figure of merit ZT of the NdxCe3-xPt3Sb4 solid so lution was found to be maximized at x = 0.35 +/- 0.10. The maximum ZT of 0. 12 at approximately 230 K, however, is too small to be useful in thermoelec tric applications. [S0163-1829(98)05044-9].