skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Thermoelectric properties optimization of Fe{sub 2}VGa by tuning electronic density of states via titanium doping

Abstract

We report the correlation between thermoelectric properties and electronic band structure of thermoelectric Heusler alloy Fe{sub 2}V{sub 1-x}Ti{sub x}Ga by comparing experimental measurements with theoretical calculations. The electrical resistivity data show that the semiconducting-like behavior of pure Fe{sub 2}VGa is transformed to a more metallic-like behavior at x = 0.1. Meanwhile, an enhancement of the Seebeck coefficient was observed for all Ti doped specimens at elevated temperatures with a peak value of 57 μV/K for x = 0.05 at 300 K. The experimental results can be elucidated by the calculated band structure, i.e., a gradual shifting of the Fermi level from the middle of the pseudogap to the region of valence bands. With optimized doping, the thermoelectric power factor can be significantly enhanced to 3.95 mW m{sup −1} K{sup −2} at room temperature, which is comparable to the power factors of Bi{sub 2}Te{sub 3}-based compounds. The synergy of thermal conductivity reduction due to the alloying effect and the significant increase of the thermoelectric power factor leads to higher order zT values than that of prime Fe{sub 2}VGa.

Authors:
 [1]; ;  [1];  [2];  [2]
  1. Institute of Physics, Academia Sinica, 11529 Taipei, Taiwan (China)
  2. Department of Physics, National Taiwan University, 10617 Taipei, Taiwan (China)
Publication Date:
OSTI Identifier:
22492867
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 118; Journal Issue: 16; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BISMUTH TELLURIDES; DENSITY OF STATES; DOPED MATERIALS; ELECTRIC CONDUCTIVITY; FERMI LEVEL; HEUSLER ALLOYS; POWER FACTOR; TEMPERATURE RANGE 0273-0400 K; THERMAL CONDUCTIVITY; THERMOELECTRIC PROPERTIES; TITANIUM

Citation Formats

Wei, Pai-Chun, Huang, Ta-Sung, Chen, Yang-Yuan, Graduate Institute of Applied Physics, National Chengchi University, 11605 Taipei, Taiwan, Lin, Shu-Wei, Guo, Guang-Yu, and Physics Division, National Center for Theoretical Sciences, 30013 Hsinchu, Taiwan. Thermoelectric properties optimization of Fe{sub 2}VGa by tuning electronic density of states via titanium doping. United States: N. p., 2015. Web. doi:10.1063/1.4934734.
Wei, Pai-Chun, Huang, Ta-Sung, Chen, Yang-Yuan, Graduate Institute of Applied Physics, National Chengchi University, 11605 Taipei, Taiwan, Lin, Shu-Wei, Guo, Guang-Yu, & Physics Division, National Center for Theoretical Sciences, 30013 Hsinchu, Taiwan. Thermoelectric properties optimization of Fe{sub 2}VGa by tuning electronic density of states via titanium doping. United States. https://doi.org/10.1063/1.4934734
Wei, Pai-Chun, Huang, Ta-Sung, Chen, Yang-Yuan, Graduate Institute of Applied Physics, National Chengchi University, 11605 Taipei, Taiwan, Lin, Shu-Wei, Guo, Guang-Yu, and Physics Division, National Center for Theoretical Sciences, 30013 Hsinchu, Taiwan. 2015. "Thermoelectric properties optimization of Fe{sub 2}VGa by tuning electronic density of states via titanium doping". United States. https://doi.org/10.1063/1.4934734.
@article{osti_22492867,
title = {Thermoelectric properties optimization of Fe{sub 2}VGa by tuning electronic density of states via titanium doping},
author = {Wei, Pai-Chun and Huang, Ta-Sung and Chen, Yang-Yuan and Graduate Institute of Applied Physics, National Chengchi University, 11605 Taipei, Taiwan and Lin, Shu-Wei and Guo, Guang-Yu and Physics Division, National Center for Theoretical Sciences, 30013 Hsinchu, Taiwan},
abstractNote = {We report the correlation between thermoelectric properties and electronic band structure of thermoelectric Heusler alloy Fe{sub 2}V{sub 1-x}Ti{sub x}Ga by comparing experimental measurements with theoretical calculations. The electrical resistivity data show that the semiconducting-like behavior of pure Fe{sub 2}VGa is transformed to a more metallic-like behavior at x = 0.1. Meanwhile, an enhancement of the Seebeck coefficient was observed for all Ti doped specimens at elevated temperatures with a peak value of 57 μV/K for x = 0.05 at 300 K. The experimental results can be elucidated by the calculated band structure, i.e., a gradual shifting of the Fermi level from the middle of the pseudogap to the region of valence bands. With optimized doping, the thermoelectric power factor can be significantly enhanced to 3.95 mW m{sup −1} K{sup −2} at room temperature, which is comparable to the power factors of Bi{sub 2}Te{sub 3}-based compounds. The synergy of thermal conductivity reduction due to the alloying effect and the significant increase of the thermoelectric power factor leads to higher order zT values than that of prime Fe{sub 2}VGa.},
doi = {10.1063/1.4934734},
url = {https://www.osti.gov/biblio/22492867}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 16,
volume = 118,
place = {United States},
year = {Wed Oct 28 00:00:00 EDT 2015},
month = {Wed Oct 28 00:00:00 EDT 2015}
}