Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates

Khabibullin, A. R.; Huan, T. D.; Nolas, G. S.; Woods, L. M.

doi:10.1016/j.actamat.2017.03.059

Title: Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates

Abstract

Inorganic clathrates with the type II crystal structure are of interest as potential materials for high temperature thermoelectric applications. In this study we present ab initio calculations for the electronic and phonon properties of several Sn type II clathrate compositions with partial Ga substitution on the framework, empty cage Sn₁₃₆, and compounds of Sn₁₃₆ filled with inert Xe atoms. It is found that cage disorder due to atomic substitution and guest encapsulation affect the fundamental characteristics of these materials in profound ways. We determine that the stability of these materials is enhanced by the presence of guests and lack of direct Ga-Ga bonds in disordered clathrates. Inert Xe atoms provide a unique opportunity to preserve the overall electronic structure of Sn₁₃₆ and take advantage of the loosely bound guest rattling for enhanced phonon scattering. The calculated energy bands and density of states, as well as phonon band structure and mode Gruneisen parameter, enable further analysis of type II Sn clathrates and reveal interesting structure-property relations.

Authors:

Khabibullin, A. R. ^[1];

^[2]; Nolas, G. S. ^[1]; Woods, L. M. ^[1]

Univ. of South Florida, Tampa, FL (United States). Dept. of Physics
Univ. of Connecticut, Storrs, CT (United States). Dept. of Materials Science & Engineering. Inst. of Materials Science

Publication Date:: Thu Mar 30 00:00:00 EDT 2017

Research Org.:: Univ. of South Florida, Tampa, FL (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:: 1533472

Alternate Identifier(s):: OSTI ID: 1398630

Grant/Contract Number:: FG02-04ER46145; FG02- 04ER46145

Resource Type:: Accepted Manuscript

Journal Name:: Acta Materialia

Additional Journal Information:: Journal Volume: 131; Journal ID: ISSN 1359-6454

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; clathrates; thermoelectric transport; electronic structure; phonon properties

Citation Formats


                    Khabibullin, A. R., Huan, T. D., Nolas, G. S., and Woods, L. M. Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates.  United States: N. p., 2017. 
Web.  doi:10.1016/j.actamat.2017.03.059.

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                    Khabibullin, A. R., Huan, T. D., Nolas, G. S., & Woods, L. M. Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates.  United States.  https://doi.org/10.1016/j.actamat.2017.03.059

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                    Khabibullin, A. R., Huan, T. D., Nolas, G. S., and Woods, L. M. Thu .  
"Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates".  United States.  https://doi.org/10.1016/j.actamat.2017.03.059.  https://www.osti.gov/servlets/purl/1533472.

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@article{osti_1533472,

  title        = {Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates},

  author       = {Khabibullin, A. R. and Huan, T. D. and Nolas, G. S. and Woods, L. M.},

  abstractNote = {Inorganic clathrates with the type II crystal structure are of interest as potential materials for high temperature thermoelectric applications. In this study we present ab initio calculations for the electronic and phonon properties of several Sn type II clathrate compositions with partial Ga substitution on the framework, empty cage Sn136, and compounds of Sn136 filled with inert Xe atoms. It is found that cage disorder due to atomic substitution and guest encapsulation affect the fundamental characteristics of these materials in profound ways. We determine that the stability of these materials is enhanced by the presence of guests and lack of direct Ga-Ga bonds in disordered clathrates. Inert Xe atoms provide a unique opportunity to preserve the overall electronic structure of Sn136 and take advantage of the loosely bound guest rattling for enhanced phonon scattering. The calculated energy bands and density of states, as well as phonon band structure and mode Gruneisen parameter, enable further analysis of type II Sn clathrates and reveal interesting structure-property relations.},

  doi          = {10.1016/j.actamat.2017.03.059},

  journal      = {Acta Materialia},

  number       = ,

  volume       = 131,

  place        = {United States},

  year         = {Thu Mar 30 00:00:00 EDT 2017},

  month        = {Thu Mar 30 00:00:00 EDT 2017}

}

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Title: Cage disorder and gas encapsulation as routes to tailor properties of inorganic clathrates

Abstract

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