Thermoelectric properties of Zn4Sb3 prepared by hot pressing

Polycrystalline specimens of the thermoelectric material Zn4Sb3 were prepared by the hot-pressing method at various temperatures and pressures and their thermoelectric properties were evaluated in a temperature range from 298 K to 673 K. A single phase of Zn4Sb3 was obtained in the samples prepared at 673 K with a pressure above 150 MPa, whereas ZnSb was placed in the Zn4Sb3 matrix for the samples prepared at 100 MPa. The electrical transport properties of the single phase compound showed p-type conduction and metallic transport behavior based on the temperature dependence. The sample produced at 673 K under a pressure of 200 MPa exhibited the highest ZT value of 1.36 at 673 K. This study suggests that the dense and single-phase Zn4Sb3 compound is a route to achieve a high thermoelectric performance.