▎ 摘　　要

Multilayered van der Waals (vdW) vertical heterostructures are a promising avenue for combining different two-dimensional materials to achieve desirable properties for numerous optoelectronic applications. To improve our understanding of how the stacking order can affect the physical properties of these systems, we present a density functional theory study of the energetic, electronic, and optical properties of vdW heterostructures of graphene (Gr)-transition-metal dichalcogenides (TMDs), namely, monolayer (graphene, MoS2, and WS2), bilayer, and tetralayer systems. We found that the Gr-TMD interactions are dominated by mainly vdW interactions, while the TMD-TMD systems also display a weak hybridization contribution of out-of-plane orbitals, which enhances the binding energy. An analysis of the bilayer electronic structure reveals that a stronger interaction induces small band gap deviations from Andersons rule. Thus, the key effect of the stacking order in tetralayer systems is primarily to control the level of interaction between TMD layers, thereby controlling the TMD band gap. The application of pressure in the direction of layer stacking can intensify this effect, as it affects the degree of interaction between TMD layers. The optical response can be well described by the sum of the response of the individual monolayers; however, minor effects were noticeable upon application of external pressure, particularly in the 3-4 eV range. Based on this, we can employ both the stacking order, controllable via growth conditions of the material, as well as pressure to control the interaction between layers and thereby tune the electronic properties of multilayered vdW heterostructures to suit various applications.