Investigation Of PSi/MoS₂ And Silicene/MX₂?M=Mo,W;X=S,Se? On Electronic Structure As Well As Transport Property

Nowadays,two-dimensional?2D?nanomaterials have drawn much attention in the field of semiconductor devices.On the basis of this,researchers have designed and developed many new types of semiconductor materials,such as two-dimensional nano-scale devices with intercalated structures or heterostructures.Two-dimensional transition metal chalcogenides?TMDCs?MX₂?M=Mo,W;X=S,Se?are widely focused because of their excellent semiconductor properties and their own structural features that contribute to the formation of composite structures with van der Waals forces.In order to explore some new types of functional composite materials which are more valuable,a series of intercalation compounds?PSi?_n/MoS₂,(PSi^mB)_n/MoS₂,and(PSi^mP)_n/MoS₂ as well as heterostructures of Silicene/MX₂?M=Mo,W;X=S,Se?were built to investigate electronic structure and transport properties based on density functional theory?DFT?and non-equilibrium Green function?NEGF?.At first,this paper studied the electronic structures and transport properties of intercalation compounds consisting of polysilane?PSi?chains with undoped and doped B,P and MoS₂ layer.By calculating the Bulk and Device systems,it was found that the conductivity gradually heightens with increasing the number of undoped PSi chain.The B-doping further increases the conductivity by introducing typical p-type semiconductor character while the P-doping introduces typical n-type semiconductor feature.The B-doping and P-doping upon PSi have significant influences on transport properties of PSi/MoS₂ intercalation compounds while heavy doping is not beneficial in increasing the conductivity.Moreover,sandwiching a large content of undoped or doped PSi is favorable in enhancing the conductivity.Overall,intercalating light B-doped or P-doped PSi into MoS₂ interlaminar spaces with large amount is an effective strategy for achieving p-or n-type semiconductor nanocomposites.Secondly,the electronic structures,the transport properties and photocurrent of four two-dimensional?2D?heterostructures silicene?SE?/MX₂?M=Mo,W;X=S,Se?were investigated.It was found that the stabilities of SE are obviously improved after being placed to the MX₂?M=Mo,W;X=S,Se?surfaces.The conductivity of the substrate non-metallic substrate is also significantly improved.Especially,SE/WS₂and SE/WSe₂ appear a novel phenomenon in terms of the negative differential resistance?NBR?behavior.In addition,the phenomenon of photoelectric effect?PGE?occurs when the double-probe system is irradiated with linearly polarized light without bias voltage,which provides some clues for the application of heterostructures in optoelectronic devices for the most conditional test.