Restructured single parabolic band model for quick analysis in thermoelectricity

The single parabolic band (SPB) model has been widely used to preliminarily elucidate inherent transport behaviors of thermoelectric (TE) materials, such as their band structure and electronic thermal conductivity, etc. However, in the SPB calculation, it is necessary to determine some intermediate variables, such as Fermi level or the complex Fermi-Dirac integrals. In this work, we establish a direct carrier-concentration-dependent restructured SPB model, which eliminates Fermi-Dirac integrals and Fermi level calculation and emerges stronger visibility and usability in experiments. We have verified the reliability of such restructured model with 490 groups of experimental data from state-of-the-art TE materials and the relative error is less than 2%. Moreover, carrier effective mass, intrinsic carrier mobility and optimal carrier concentration of these materials are systematically investigated. We believe that our work can provide more convenience and accuracy for thermoelectric data analysis as well as instructive understanding on future optimization design.

Advanced thermoelectrics governed by a single parabolic band: Mg2Si0.3Sn0.7, a canonical example

Enhanced thermoelectric performance of Bi-doped Mg2Si0.3Sn0.7 with conduction band convergence has been successfully interpreted using the single parabolic band (SPB) model. The improved understanding of scattering parameters is important and instructive for further optimization of n-type Mg2Si0.3Sn0.7.