Herein, we report a method for structural characterization as well as TE properties measurements of individual single-crystalline Lead telluride (PbTe) NWs by employing a new microchip design. In this work, the single PbTe NW was characterized in four different types of measurement: structural characterization, Seebeck coefficient S, electrical conductivity σ, and thermal conductivity κ. The structural characterization by transmission electron microscope (TEM) revealed that the PbTe NWs were high-quality single crystals with a growth along the [100] direction. The TE properties S, σ, and κ measurement results of individual 75 nm PbTe NW at room temperature were −54.76 µV K−1, 1526.19 S m−1, and 0.96 W m−1 K−1, respectively. Refer to the result of S, σ and κ; the figure of merit ZT values of a 75 nm PbTe NW at the temperature range of 300‒350 K were 1.4‒4.3 x 10−3. Furthermore, it was observed that the κ value is size-dependent compared to previous reported, which indicates that thermal transport through the individual PbTe NWs is limited by boundary scattering of both electrons and phonons. The results show that this new technique measurement provided a reliable ZT value of individual NW yielded high accuracy for size-dependent studies.
Part of the book: Impact of Thermal Conductivity on Energy Technologies