Theoretical study of MoTe₂/MoSi₂As₄ van der Waals heterostructures for photoelectric applications

Abstract The stacking of two-dimensional materials to form van der Waals heterostructures (vdWHs) creates new opportunities for multifunctional devices applications. Here, the MoTe 2 /MoSi 2 As 4 vdWHs are designed to explore their potential properties under an applied electric field. The MoTe 2 /MoSi 2 As 4 vdWHs exhibit an indirect band structure with a straddling band alignment. Upon application of a certain positive electric field, the band alignment dynamically transitions from a straddling gap to a staggered configuration, accompanied by enhanced interlayer charge separation. The MoTe 2 /MoSi 2 As 4 vdWHs demonstrates potential as an efficient two-dimensional excitonic solar cell, achieving a power conversion efficiency of up to 15.98%. The high optical absorption coefficient and high power conversion efficiency of MoTe 2 /MoSi 2 As 4 vdWHs indicate the potential value of MoTe 2 /MoSi 2 As 4 vdWHs in photovoltaic applications such as solar cells and photodetectors. Our results open a new pathway for multifunctional vdWHs devices by the synergistic interaction of MoTe 2 and MoSi 2 As 4 monolayers, thus providing theoretical support for the application of MoTe 2 /MoSi 2 As 4 vdWHs in high-efficiency solar cells and photodetectors.