Interplay between metavalent bonds and dopant orbitals enables the design of SnTe thermoelectrics.

ABSTRACT: Engineering the electronic band structures upon doping is crucial to improve the thermoelectric performance of materials. Understanding how dopants influence the electronic states near the Fermi level is thus a prerequisite to precisely tune band structures. Here, we demonstrate that the Sn-s states in SnTe contribute to the density of states at the top of the valence band. This is a consequence of the half-filled p-p σ-bond (metavalent bonding) and its resulting symmetry of the orbital phases at the valence band maximum (L point of the Brillouin zone). This insight provides a recipe for identifying superior dopants. The overlap between the dopant s- and the Te p-state is maximized, if the spatial overlap of both orbitals is maximized and their energetic difference is minimized. This simpl

SUBMITTER: Tang G 

PROVIDER: S-EPMC11500016 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature