Electron-phonon coupling and thermal transport in the thermoelectric compund Mo<sub>3</sub>Sb<sub>7-x</sub>Te<sub>x</sub> [electronic resource].
- Published:
- Washington, D.C. : United States. Dept. of Energy. Office of Basic Energy Sciences, 2015.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy - Physical Description:
- Article numbers 214,301 : digital, PDF file
- Additional Creators:
- Argonne National Laboratory, United States. Department of Energy. Office of Basic Energy Sciences, and United States. Department of Energy. Office of Scientific and Technical Information
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- Restrictions on Access:
- Free-to-read Unrestricted online access
- Summary:
- Phonon properties of Mo3Sb7-xTex (x = 0,1.5,1.7), a potential high-temperature thermoelectric material, have been studied with inelastic neutron and x-ray scattering, and with first-principles simulations. The substitution of Te for Sb leads to pronounced changes in the electronic structure, local bonding, phonon density of states, dispersions, and phonon lifetimes. Alloying with tellurium shifts the Fermi level upward, near the top of the valence band, resulting in a strong suppression of electron-phonon screening and a large overall stiffening of interatomic force constants. The suppression in electron-phonon coupling concomitantly increases group velocities and suppresses phonon scattering rates, surpassing the effects of alloy-disorder scattering and resulting in a surprising increased lattice thermal conductivity in the alloy. We also identify that the local bonding environment changes nonuniformly around different atoms, leading to variable perturbation strengths for different optical phonon branches. Here, changes in phonon group velocities and phonon scattering rates are quantified, highlighting the large effect of electron-phonon coupling in this compound.
- Report Numbers:
- E 1.99:1245023
- Subject(s):
- Note:
- Published through SciTech Connect.
12/07/2015.
"125686"
Physical Review. B, Condensed Matter and Materials Physics 92 21 ISSN 1098-0121 AM
Dipanshu Bansal; Chen W. Li; Ayman H. Said; Douglas L. Abernathy; Jiaqiang Yan; Olivier A. Delaire. - Funding Information:
- AC02-06CH11357
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