Multiscale simulation study on the mechanical, electrical, and thermal properties of ZnSb semiconductor

Abstract

This study presents a comprehensive investigation of the multifunctional properties of ZnSb semiconductors through integrated multiscale simulations. A highly accurate interatomic potential function for ZnSb was constructed and validated using density functional theory (DFT) and deep potential (DP) methods within the temperature range of 300 K to 800 K. Molecular dynamics (MD) simulations revealed the mechanical behavior of ZnSb along different crystallographic axes. The a-axis exhibited significant plastic deformation with a fracture strain of 32%, while the b-axis and c-axis demonstrated brittle fracture characteristics. As the temperature increased from 300 K to 700 K, both the elastic modulus and ultimate strength decreased significantly, indicating the detrimental effect of high temperatures on its mechanical properties. Simulations of thermoelectric performance showed that optimizing carrier concentration can significantly improve the power factor (PF). Electronic thermal conductivity (κ_e) increases with carrier concentration and temperature, but the Seebeck coefficient performs better at lower carrier concentrations. Thermal transport analysis revealed that the lattice thermal conductivity of ZnSb initially decreases and then increases with rising temperature, with the contribution of Sb–Sb bonds to thermal conductivity exceeding 50%. This study provides a theoretical foundation for the application of ZnSb materials in thermoelectric conversion and high-temperature devices, and highlights the key parameters for performance optimization.