Twist angle dependent electronic properties in 2D graphene/MoS2vdW heterostructures

Abstract

Two-dimensional (2D) heterostructures constructed by different 2D materials offer new opportunities for novel nano-devices. Twist angle (θ) between two individual layers in 2D van der Waals (vdW) heterostructures shows great importance in modulating their electronic properties. Here, we performed first-principles calculations to study the thermodynamic stability and electronic properties of graphene/MoS2 (Gr/MoS2) vdW heterostructures. We have built dozens of possible Gr/MoS2 vdW heterostructures under the limitation of the maximum mismatch (δ ≤ 2.5%) and supercell lattice (≤20 Å). We found the cohesive energy (Ecoh) is dependent on the interlayer distance and θ. In addition, a huge difference can be found in both the band offset and interlayer carrier's lifetime of Gr/MoS2 with different θ. These results provide valuable insights into the identification of these twist structures in experiments and the designation of Gr/MoS2 related optoelectronic devices.