Nanoscale inclusions in the phonon glass thermoelectric material Zn_4Sb_3

摘要

We have investigated the thermoelectric material Zn_4Sb_3 using transmission electron microscopy (TEM). Nanoscale inclusions with a diameter of about 10nm were observed, constituting on the order of 1 percent by volume of the material. Studies using energy filtered imaging, electron diffraction, and high-angle annular dark-field STEM indicate that the inclusions consist of Zn. These inclusions are expected to scatter the medium and long-wavelength phonons effectively, thus contributing to phonon glass behavior which results in the exceptionally low thermal conductivity for this thermoelectric material.