Thermoelectric properties of dense bulk polycrystalline In 4Se3-x (x = 0, 0.25, 0.5, 0.65, and 0.8) compounds are investigated. A peak dimensionless thermoelectric figure of merit (ZT) of about 1 is achieved for x = 0.65 and 0.8. The peak ZT is about 50% higher than the previously reported highest value for polycrystalline In4Se 3-x compounds. Our In4Se3-x samples were prepared by ball milling and hot pressing. We show that it is possible to effectively control the electrical conductivity and thermal conductivity by controlling selenium (Se) deficiency x. The ZT enhancement is mainly attributed to the thermal conductivity reduction due to the increased phonon scattering by Se deficiency, defects, and nanoscale inclusions in the ball-milled and hot-pressed dense bulk In4Se3-x samples.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Mar 4 2011|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics