When band convergence is not beneficial for thermoelectrics

  title={When band convergence is not beneficial for thermoelectrics},
  author={Junsoo Park and Maxwell Thomas Dylla and Yi Xia and Max Wood and Gerald Jeffrey Snyder and Anubhav Jain},
  journal={Nature Communications},
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… 
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