Work

Thermoelectric performance of Zn-substituted type-VIII clathrate Ba8Ga16Sn30 single crystals

Year: 2012

Type: article

Abstract: We have grown single-crystalline samples of Zn-substituted type-VIII clathrate Ba8Ga16Sn30 with n-type carriers by Sn-flux method. The actual compositions of the single crystals were found to be described as Ba8Ga15.8−2yZnySn30.2+y (y = 0 ∼ 0.54), where the charge balance is well maintained. As y goes from 0 to 0.42, the resistivity at 300 K decreases from 5.3 to 3.0 mΩ cm gradually, but the effective mass is essentially constant at 1.2 ∼ 1.5m0, indicating intact band structure near the conduction band minima upon Zn substitution for Ga. At elevated temperatures, the ambipolar effect on the thermal conductivity becomes less pronounced upon Zn doping, and the dimensionless figure of merit ZT for y = 0.07 and 0.42 remains at rather high values compared with the nondoped sample.

Source: Journal of Applied Physics

DOI: 10.1063/1.3673863

Authors: Baoli Du, Yuta Saiga, Kousuke Kajisa, Toshiro Takabatake

Institutions: Hiroshima University, Henan Polytechnic University

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: green

Funders: Ministry of Education, Culture, Sports, Science and Technology, Japan Society for the Promotion of Science

Awards: G1424135931, G4478582688