Niobium substitution in Zr0.5Hf0.5NiSn based Heusler compounds for high power factors

This work reports on the structural and physical properties of the Heusler alloy (Zr0.5Hf0.5)(1-x)NbxNiSn with varying Nb concentrations. The structure of the (Zr0.5Hf0.5)(1-x)NbxNiSn solid solution was investigated by means of X-ray diffraction. It is found that the alloys exhibit the C1(b) structure for all Nb concentrations. The physical properties were studied using the physical properties measurement system from low temperature to room temperature. It was shown that the thermoelectric properties like the dimensionless Figure of Merit are increased five times by substituting (Zr0.5Hf0.5) with Nb to 0.09 at 300 K and the Powerfactor is increased 10 times to 1.8 mW/K-2 m at 300 K. (c) 2011 American Institute of Physics. [doi:10.1063/1.3548867]