First-principles insights of electronic properties of Blue Phosphorus/MoSi2N4 van der Waals heterostructure via vertical electric field and biaxial strain

Very recently, a new kind of 2D transition metal nitride , MoSi 2 N 4 , has been attracting considerable attention due to its successful synthesis and outstanding properties. To further explore its novel properties and applications for nanodevices , we have proposed a van der Waals (vdW) heterostructure composed of MoSi 2 N 4 and Blue Phosphorus (BlueP) monolayers and systematically studied its electronic properties with first-principles calculations. The results show that the heterostructure exhibits a type-II band alignment, with the conduction band minimum (CBM) and valence band maximum (VBM) located in BlueP and MoSi 2 N 4 layers, respectively. Furthermore, the electronic properties of heterostructure are not sensitive to different stacking patterns while can be significantly modulated by applying an external electric field or a biaxial strain. When applying the electronic field, the band gap shows linear variation with the electric field, and a semiconductor-to-metal transition is observed under the strong electric field. When applying the biaxial strain, the band alignment can be transformed from type-II to type-I. This work provides theoretical guidance for design of flexible nano-electronic and optoelectronic devices based on the BlueP/MoSi 2 N 4 heterostructure. • The BlueP/MoSi 2 N 4 heterostructure exhibits a type-II band alignment. • The electronic properties of heterostructure are not sensitive to diverse stacking patterns. • The electronic properties of heterostructure can be tuned by external electric field or biaxial strain. • A semiconductor-to-metal transition takes place when applying a strong electric field. • Band alignment transition from type-II to type-I has been observed under the effect of biaxial strain.