Transport properties of hot pressed β — Zn4Sb3 compounds

Abstract

Single phase β — Zn₄Sb₃ samples were prepared by using hot pressing method. Their structural and morphological properties were studied by x-ray diffraction analysis (XRD) and Scanning Electron Microscopy (SEM), respectively. The transport properties were obtained from Seebeck coefficient S(T) and electrical resistivity p(T) measurements between 100 and 290K. S(T) shows positive values suggesting a p-type material, its magnitude increases with the processing time, reaching maximum values close to 270μV/K. The electrical resistivity measured by four D.C. probe method, increases with processing time, however its magnitude is less than 9mΩ — cm. We observe an order-disorder transition in the transport properties around 240K, which is a characteristic property of pure single crystals of β — Zn₄Sb₃. From S(T) and p(T) experimental data we calculate the thermoelectrie power factor PF , this performance parameter reaches maximum values close to 10μW//K² — cm, which makes this kind of compounds promising materials for thermoelectric applications.