Half-metallic behavior and anisotropy of two-dimensional MoSi2N4/ 2 N 4 / ScSi2N4 2 N 4 heterojunction

Heterojunctions formed by stacking different two-dimensional monolayer materials typically have tunable electronic properties, which will greatly broaden the application prospects of 2D materials in electron devices. In this paper, the structures, electron properties, and anisotropy of MoSi2N4/ScSi2N4 2 N 4 /ScSi 2 N 4 heterojunctions formed by stacking MoSi2N4 2 N 4 monolayer with semiconductor properties and ScSi2N4 2 N 4 monolayer with half-metallic properties have been systematically studied. The results show that Type-I configuration has the most stable structure in terms of total energy, binding energy, phonon spectrum and molecular dynamics among the three configurations formed by MoSi2N4/ScSi2N4 2 N 4 /ScSi 2 N 4 heterojunctions. The MoSi2N4/ScSi2N4 2 N 4 /ScSi 2 N 4 heterojunction has robust half-metallic behavior and tensile anisotropy at equilibrium. At the same time, MoSi2N4/ScSi2N4 2 N 4 /ScSi 2 N 4 heterojunction can still maintain stable ferromagnetic and half-metallic properties under large interlayer distance changes. Studies of magnetic anisotropy show that the direction of hard axis for MoSi2N4/ScSi2N4 2 N 4 /ScSi 2 N 4 heterojunction is perpendicular to the 2D layer plane. The tunable properties of MoSi2N4/ScSi2N4 2 N 4 /ScSi 2 N 4 heterojunction provides promising exploration for novel 2D materials.