Band Structure Engineering of Black Phosphorus/Graphene/MoS₂ van der Waals Heterojunctions for Photovoltaic and Optoelectronic Device Application

In this paper, we study the band structure engineering of black phosphorus/graphene/MoS₂ (BP/graphene/MoS₂) van der Waals heterojunctions based on ab initio simulations. The density of state and charge density of BP/MoS₂, bilayer-BP/MoS₂, bilayer-BP/graphene/MoS₂ and graphene/bilayer-BP/MoS₂ heterojunctions are also investigated. It is found that the bandgaps of these four heterojunctions are smaller than the case of single layer BP or MoS₂. When graphene is inserted into or stacked upon BP and MoS₂ layers, the heterojunction can obtain a minimum bandgap and a higher density of state distribution. In the differential charge density diagram, electrons over the carbon, sulfur and phosphorus atoms are lost from those corresponding parts. These investigations based on the band structure engineering of 2D van der Waals heterojunctions can provide an effective guidance to manufacture the future nanoscale high performance photovoltaic and optoelectronic devices.