|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Nanocomposites IV: Nanoscience for Renewable Energy
||Introducing Dislocation Lines for Controlled Thermal Conductivity in Si-based Nanocomposites by Liquid-phase Sintering
||Jun Xie, Yuji Ohishi, Satoshi Ichikawa, Aikebaier Yusufu, Hiroaki Muta, Ken Kurosaki, Shinsuke Yamanaka
|On-Site Speaker (Planned)
The performance of bulk thermoelectrics can be improved by effective scattering of phonons with a wide range frequency. Many studies have focused on grain boundary and point-defect scattering in Si-based thermoelectric materials, which target low- and high-frequency phonons, while phonons with mid-frequency remain largely unaffected. In this study, high density of intragranular dislocations were formed in (Si0.97P0.03)95Co5 nanocomposites synthesized by melt-spinning technique and liquid-phase sintering. These dislocations may effectively scatter mid-frequency phonons, leading to a 50% reduction of κlat compared with a normally sintered sample without high density of dislocations. Stronger phonon scattering with minimal carrier scattering achieved a peak ZT of 0.39 at 1070 K without alloying any expensive and rare Ge. The morphology and formation mechanism of dislocations were investigated by utilizing X-ray diffraction, scanning electron microscopy and transmission electron microscopy observations. The influences on the thermoelectric properties of the dislocation lines will be discussed in detail.
||Planned: Supplemental Proceedings volume