High performance in room temperature and thermoelectric properties of PbSe single crystal prepared by Pb-flux method

Abstract

In this study, PbSe single crystal with the grain size of 10 mm was prepared using Pb-flux method combined with melt slow cooling process, and its structure and thermoelectric transportation properties were systematically studied. X-Ray powder diffraction results indicated that all prepared samples has a NaCl-type crystal structure with a space group of Fm3¯m. Transmission electron microscopy and the corresponding selected area electron diffraction results illustrated that the sample prepared by this method was a single crystal. Thermal analysis showed insignificant weight loss in the PbSe sample below the melting point, thereby indicating that PbSe has good thermal stability. X-Ray photoelectron spectroscopy results demonstrated that the valences of Pb and Se were +2 and −2, respectively. Given that the PbSe sample had a high mobility, the material has a high electrical conductivity near room temperature. Thus, the ZT value near room temperature reaches 1.25, which indicates that single crystal PbSe obtained by Pb flux method has potential application in room-temperature power generation.