Metavalent alloying and vacancy engineering enable state-of-the-art cubic GeSe thermoelectrics.

ABSTRACT: Conventional alloying strategies often require high alloying concentrations, leading to impurity phases and additional phase transition that limit the figure of merit of thermoelectric materials. Here, we introduce metavalent alloying and vacancy engineering as transformative strategies to facilitate the orthorhombic-to-cubic phase transition, in which we stabilize pure cubic GeSe under ambient conditions with just 10% alloying concentration using Sb₂Te₃ as an effective alloying agent. Compared to the covalently bonded orthorhombic phase, the metavalently bonded cubic GeSe features lower cation vacancy formation energy, reduced bandgap, enhanced band degeneracy, weaker chemical bonding, stronger lattice anharmonicity, and multiple phonon scattering centers. These prop

SUBMITTER: Luo H 

PROVIDER: S-EPMC11961766 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature