Low temperature transport and thermal properties of half-Heusler alloy Zr0.25Hf0.25Ti0.5NiSn

The half-Heusler alloy Zr0.25Hf0.25Ti0.5NiSn was studied by electrical resistivity, Seebeck coefficient, Hall effect, thermal conductivity, and specific heat measurements, performed in the temperature range 2-300 K. The transport properties in all temperature range show that the alloy is a narrow-gap semi-conducting material with good thermoelectric efficiency, the value of the figure of merit about 0.094 near room temperature. The multi-component in the alloy increases the atomic disorder between Ti and Zr (Hf, Sn) atoms, which has a strong influence on the electrical transport behaviors and the thermoelectric properties. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved.