Synthesis of Mg₂Si_1−X Ge _X solid-solution nanostructures by thermal annealing of CaSi₂ crystal powders with Ge and MgCl₂/Mg

Abstract

Mg2Si1-XGeX solid-solution nanostructures, a collection of nanoparticles in the form of polycrystalline sheet, were synthesized by thermal annealing of CaSi2 crystal powders with Ge/MgCl2 mixed powders and Mg balls. The Ca atoms were extracted from CaSi2 crystals to synthesize a nanostructure. Subsequently, the Ge atoms were transported into the Si nanostructures by selective etching of Si and Ge, and Mg was incorporated from the Mg atmosphere. Concentration of Ⅹ (Ge composition) was varied in the Mg2Si1-XGeX solid-solution nanostructures at the given process conditions and storage environment. The homogeneity of Ⅹ-concentration in the nanostructure improved with increasing annealing temperature. Effect of the annealing temperature on the structural properties of the nanostructure was examined.