High-temperature thermoelectric properties of Tix(ZrHf)0.99-xV0.01Ni0.9Pd0.1Sn0.99Sb0.01 half-Heusler alloys

The effect of Ti substitution at the Zr and Hf site on thermoelectric properties of Ti-x(ZrHf)(0.99-x)V0.01Ni0.9Pd0.1Sn0.99Sb0.01 half-Heusler alloy compounds was investigated by finding the electrical resistivity, Hall effect, Seebeck coefficient, thermal conductivity and using X-ray diffraction. It was shown that substitution of Ti for Zr and Hf leads to a major reduction in the thermal conductivity and an enhancement of the Seebeck coefficient. The observed maximum Seebeck coefficient, minimum electrical resistivity, and minimum thermal conductivity at about 820 K are 206 mu V K-1, 0.71 m Omega cm, and 5.13 W m(-1) K-1, respectively. In addition, the dimensionless figure of merit is about 0.92 at about 820 K with a Ti content at x=0.3. (C) 2010 Elsevier B.V. All rights reserved.