Ultrahigh power factor of Bi/Zn co-doped SnSe: Mechanical and thermoelectric properties on DFT level

Abstract

Tin selenide-based materials have attracted much attention recently because of their unique properties. This study employs first-principles calculations and density functional theory (DFT) to investigate the impact of Bismuth and Zinc co-doping on the electronic, mechanical, and thermoelectric properties of SnSe. The co-doped system exhibits a triclinic crystal structure and shows enhanced electrical conductivity and the generation of n-type carriers. The co-doped SnSe also demonstrates improved mechanical stability, higher susceptibility to shear deformation, and increased deformability under shear stresses. Thermoelectric calculations reveal significantly enhanced power factor (PF) values compared to pristine SnSe and single-doped Zn and Bi SnSe structures, with a maximum PF of 63.0 μV/Kcm at 800 K. These findings highlight the potential of Bi and Zn co-doped SnSe as a promising high-performance thermoelectric material and provide valuable insights for further research in SnSe-based materials.