Realizing High Thermoelectric Performance of Materials via Nanostructure Engineering

Cheng-Lung Chen^1*, V. K. Ranganayakulu¹, Maw-Kuen Wu¹, Yang-Yuan Chen¹

¹Institute of Physics, Academia Sinica, Taipei, Taiwan

* Presenter:Cheng-Lung Chen, email:clchen0417@gmail.com

Thermoelectric materials, capable of realizing heat and electricity conversion, have shown great potential applications in renewable energy and wearable electronics. Materials with a high thermoelectric figure of merit (ZT) should have both a high Seebeck coefficient and a high electrical conductivity, but a low thermal conductivity. Utilizing nanotechnology to further enhance the ZT of traditional thermoelectric materials has triggered active research and created lots of exciting results. In this talk, I will first show the ZT enhancement of Bi₂Te₃ and MgAgSb nanocomposites by adding silicate aerogel, and demonstrate that the aerogel introduced strained boundaries, amorphous/crystalline interfaces, planar defects, and mesoscale boundaries not only effectively suppresses the phonon propagation but also selectively scatters carriers within materials. I will also report the recent systematic studies on Sb and Bi-Sb codoping GeTe single crystals, and reveal the unique nanostructures caused by doping play an important role in wide-frequency phonon scattering, thereby promoting GeTe become the first echelon of cutting-edge thermoelectric materials.

Keywords: Nanocomposites, Thermoelectric, Energy , Phonon, Nanotechnology