When band convergence is not beneficial for thermoelectrics.

ABSTRACT: Band convergence is considered a clear benefit to thermoelectric performance because it increases the charge carrier concentration for a given Fermi level, which typically enhances charge conductivity while preserving the Seebeck coefficient. However, this advantage hinges on the assumption that interband scattering of carriers is weak or insignificant. With first-principles treatment of electron-phonon scattering in the CaMg₂Sb₂-CaZn₂Sb₂ Zintl system and full Heusler Sr₂SbAu, we demonstrate that the benefit of band convergence can be intrinsically negated by interband scattering depending on the manner in which bands converge. In the Zintl alloy, band convergence does not improve weighted mobility or the density-of-states effective ma

SUBMITTER: Park J 

PROVIDER: S-EPMC8187731 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature