First-principles study on band structures and electrical transports of doped-SnTe

Tin telluride is a thermoelectric material that enables the conversion of thermal energy to electricity. SnTe demonstrates a great potential for large-scale applications due to its lead-free nature and the similar crystal structure to PbTe. In this paper, the effect of dopants (i.e., Mg, Ca, Sr, Ba, Eu, Yb, Zn, Cd, Hg, and In) on the band structures and electrical transport properties of SnTe was investigated based on the first-principles density functional theory including spin–orbit coupling. The results show that Zn and Cd have a dominant effect of band convergence, leading to power factor enhancement. Indium induces obvious resonant states, while Hg-doped SnTe exhibits a different behavior with defect states locating slightly above the Fermi level.

Graphical abstractThe effects of ten different dopants on the band structure and electrical transport of SnTe were investigated from first-principles calculations. Cadmium and Zinc were found to have the most significant band convergence effect leading to an enhancement in power factor. Indium induces obvious resonant states, while Hg-doped SnTe exhibits a different behavior with defect states locating slightly above the Fermi level.Figure optionsDownload full-size imageDownload as PowerPoint slide