First-Principles Study And Preparation Of Photoelectric Modified Of Graphene/MoS₂ Heterojunction

Since the graphene was discovered,the heat of two-dimensional materials research has remained constantly,and various of two-dimensional materials which were based on graphene have been developed by researchers in various fields.Among them,graphene/MoS2heterojunction combines the well photoelectric properties of graphene and MoS2,being expected to become a new material that can replace traditional silicon in semiconductor field.Besides,at present,Graphene/MoS2 heterojunctionthe has been in an initial stage between theoretical calculation and fabrication.The individuals who have researched on the structure is less and the photoelectric characteristics of the heterojunction has been in the stage of uncontrollable currently.The paper is based on the First-Principle DFT theory.Initially,they constructed the nine theoretical models via exerting the press to change the Graphene/MoS2 heterojunction layer spacing,at the beginning of the theory and combining the previous research results.Then,the electronic structure and optics of it were modified via the method of doping halogen elements and periodic stacking.Ultimately,they used CVD method to lining-up graphene thin films and Graphene/MoS2 heterojunction in order to research the different process parameters influence on sample layer number and surface topography.And it characterized and analyzed thin film via SEM and Raman method.It can be calculated and analyzed that,in nine different Graphene/MoS₂ heterojunction models,the Mo atom has the highest stability corresponding to the central position of the lower graphene carbon ring structure.The energy gap is opened to 13meV,and the photoelectric conversion effect is the best.The interlamellar spacing changing can largely regulate and control band gap of Graphene/MoS2 heterojunction that can be opened to35meV.The heterojunction decreased with the increasing periodic layer number,and the dielectric constant intensity increased with increasing of the layers number.The doping of halogen elements can greatly improve the energy band structure near the dirac point of graphene,and increase the absorption property of infrared light.The discovery of preparation of heterojunction via CVD,when it was found by CVD that the deposition effect of graphene was the best when the temperature was 900?and the flow ratio of hydrogen to methane was1:1.And molybdenum disulfide was prepared by 10mins gained the better film morphology.