Reducing the lattice thermal conductivity of the rocksalt I-V-VI$_{2}$ compounds

ORAL

Abstract

Reducing the lattice thermal conductivity is a crucial task in the optimization of the thermoelectric figure of merit. Recent theoretical calculations [1] have revealed the presence marginally stable acoustic phonons which have extremely large Gr\"{u}nesien parameters which result in a strong anharmonicity in heat-carrying acoustic phonon branches of select rocksalt I-V-VI2 compounds as a result of lone pair electrons on group V elements. Here, we present a new simple method of mapping Gr\"{u}nesien parameters, using readily available information on the ionization and the hybridization of the chemical bonds involved, and avoiding extensive numerical simulations. Additionally, we present current advances in doping on alkali based compounds which have inexpensive and non-toxic starting constituents. \\[4pt] [1] Michele D. Nielsen, Vidvuds Ozolins and Joseph P. Heremans, Lone pair electrons minimize lattice thermal conductivity, Energy Environ. Sci., 6, 570 -- 578 (2013)

*This work is supported as part of the ``Revolutionary Materials for Solid State Energy Conversion (RMSSEC),'' an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science.

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Authors

  • Michele Nielsen

    • Department of Mechanical and Aerospace Engineering, Ohio State University, Columbus, Ohio 43210

  • Sunphil Kim

    • Department of Mechanical and Aerospace Engineering, Ohio State University, Columbus, Ohio 43210

  • Matthias Wuttig

    • I. Physikalisches Institut (IA), RWTH Aachen University, 52056 Aachen, Germany

  • Felix Lange

    • I. Physikalisches Institut (IA), RWTH Aachen University, 52056 Aachen, Germany

  • Joseph P. Heremans

    • 1 Department of Mechanical Engineering, The Ohio State University, Columbus, OH; 2 Department of Physics, The Ohio State University, Columbus OH
    • Ohio State University
    • Department of Mechanical and Aerospace Engineering, Department of Physics, Ohio State University, Columbus, Ohio 43210
    • The Ohio State University
    • Department of Mechanical and Aerospace Engineering, Department of Physics. Ohio State University