Effects of Single Doping and Composite Doping of Yttrium and Antimony on the Structural, Thermodynamic, Mechanical, and Electronic Properties of Mg2Si by First Principles

Abstract

The structural, stability, thermodynamic, mechanical, and electronic properties of Y and Sb doped into Mg2Si were studied by first principles. The results show that the stable structures are Mg7Si4Y, Mg8Si4Sb, Mg6Si4YSb, and Mg7Si4YSb. Mg8Si4Sb has the largest ductility among them. Y doping causes strong orbital hybridization between Mg (2p) and Y (4d), while Sb doping causes strong orbital hybridization between Mg (2p), Si (3p), and Sb (5p). However, the thermal conductivity and hardness of Mg2Si will be reduced by Y and Sb doping. The conductivity of Mg8Si4Sb is the best. The anisotropy of the {100}, {010}, and {001} surfaces will increase once doped with Y or Sb. Mg8Si4Sb has the highest degree of anisotropy.