Enhancement of thermoelectric figure of merit by pressure-driven electronic topological transition

ORAL

Abstract

The world is currently facing a state of energy shortage, and thus the alternative green energy is ultimately in demand. Thermoelectric generators, which can generate electricity directly from waste heat with the advantages of reliability and compactness, are considered as potential devices for waste heat recovery. The thermoelectric performance is usually evaluated by a parameter named as the figure of merit zT. So far, the maximum zT at room temperature has remained around 1.0 over sixty years. For practical technological applications, it is highly desired to break this barrier. Here, we choose a Cr doped PbSe with the maximum zT less than 1.0 at high temperature of about 700 K. By simply applying external pressure, we obtain the record high zT value of 1.74 at room temperature. Pressure-driven electronic topological transition is proposed to account for such a huge enhancement. These results and findings point to a new direction in the improvement of zT in the existing thermoelectric materials through the lattice compression.

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Presenters

  • Liucheng Chen

    • Center for High Pressure Science & Technology Advanced Research
    • Center for High Pressure Science and Technology Advanced Research

Authors

  • Liucheng Chen

    • Center for High Pressure Science & Technology Advanced Research
    • Center for High Pressure Science and Technology Advanced Research

  • Pei-Qi Chen

    • Science, Mathematics, Computer Science Program,Poolesville High School

  • Viktor V Struzhkin

    • Geophysical Laboratory, Carnegie Institution of Washington

  • Alexander Goncharov

    • Geophysical Laboratory, Carnegie Institution of Washington

  • Qian Zhang

    • Department of Physics and TcSUH University of Houston

  • Zhifeng Ren

    • University of Houston
    • Department of Physics and TcSUH University of Houston
    • The Texas Center for Superconductivity, University of Houston

  • Xiao-Jia Chen

    • Center for High Pressure Science & Technology Advanced Research
    • Center for High Pressure Science and Technology Advanced Research
    • Center for High-Pressure Science & Technology Advanced Research
    • Center for High Pressure Science and Technology Advanced Research, Shanghai