ICT2014 Abstracts

As part of our collaboration with Total/Hutchinson we aim to select, synthesize, characterize and shape thermoelectric materials in the temperature range 300-500 °C. One of the good candidates is ZnSb which is known for quite some time as a p-type thermoelectric material. Despite its high Seebeck coefficient and its thermal stability it has aroused less consideration than b-Zn₄Sb₃ due to its high thermal conductivity.

In this study we present two ways of synthesis for ZnSb. The first route, involves melting, quenching and annealing which is the process mostly used in the literature. The second route is mechanical alloying, which may allow to decrease the thermal conductivity  by nanostructuration after the shaping process.

The chemical and microstructural characterizations are made by X-Ray diffraction, differential scanning calorimetry, and SEM/EDS analysis.

Both processes are followed by hot pressing and Spark Plasma Sintering in order to reach the highest density for good thermoelectric characterizations: Seebeck coefficient, electrical resistivity and Hall measurement are performed at room temperature.

We also present attempts of doping ZnSb, following these two paths, in order to achieve n-type conductivity.