We investigated the thermoelectric properties of Al and Bi co-doped Mg2Si polycrystalline bulks fabricated using a solid state reaction combined with the spark plasma sintering technique. Through controlled doping of Al and Bi, the power factor could be enhanced due to an increase in the Seebeck coefficient benefiting from an enhancement of the density of states effective mass. The lattice thermal conductivity was reduced due to intensified point-defect phonon scattering originating from the mass difference between the host Si atoms and Bi dopants. By these synergetic effects, the dimensionless figure of merit (ZT) of 1.02 was obtained at 873 K.
Bibliographical noteFunding Information:
This work was supported by Hyundai Motor Company ( 2015-11-0146 ), the Korea government ( MSIP ) ( 2014R1A2A1A10053869 ), and the Priority Research Centers Program ( 2009-0093823 ) through the National Research Foundation of Korea ( NRF ), and the Industrial Fundamental Technology Development Program ( 10052977 ) funded by the Ministry of Trade, Industry and Energy ( MOTIE ) of Korea.
© 2016 Elsevier Ltd. All rights reserved.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys