Study On Basic Physical Properties And Modulation Mechanism Of GaN Monolayer

Since the successful preparation of two-dimensional graphene materials,a large number of two-dimensional materials have attracted a lot of scientists due to their novel properties and potential applications.Two-dimensional Gallium Nitride(GaN)material,as the representative of two-dimensional materials in group ? nitrides,has a graphene-like structure and has been successfully prepared by experiments.Due to the indirect band gap and non-magnetism of GaN monolayer,many modifications have been used to modulate these properties.Functionalization has a great influence on the electronic structure and optical properties of GaN monolayers.However,there is a lack of systematic theoretical research on the structural,electronic and optical properties of GaN monolayers after functionalization.Method based on first principles,this paper systematically studied the basic physical properties and functionalization modulation GaN monolayers after single layer structure,properties and the electronic structure and optical properties of GaN monolayers after from the electronic and atomic level reveals the functional mechanism of electronic structure and optical properties of single layer,and based on its nature further determine functionalized GaN single-layer potential in the field of industrial applications.It can be summarized as follows:Based on the first-principle pseudopotential method,the structure models of GaN monolayers after hydrogenation and fluorination were constructed.The stability of the functionalized GaN monolayers was analyzed from the perspective of mechanics and dynamics.All the functionalized GaN monolayers except semi-fluorinated GaN monolayer were stable.It is found that the electronic structure of GaN monolayers can be easily modulated by functionalized by analyzing the main composition,band gap size and type of band gap by state density and band structure.Then,quantitative charge transfer analysis shows that there is a large amount of charge transfer on GaN monolayers,which results in the change of planar structure into wrinkled structure.In addition,functionalization can improve the work function of GaN monolayers,so the functionalized GaN monolayers may form ohmic contact with some metals.Finally,the real part and light absorption spectrum of functionalized GaN monolayers are calculated.The results show that the light absorption of GaN monolayers in the visible region is significantly enhanced by semi-hydrogenation.Based on the modulation mechanism of functionalization on the electronic structure and optical properties of GaN monolayers,this study proposes that semihydrogenated GaN monolayer is a potential new optoelectronic material,which provides guidance for the preparation of GaN monolayer optoelectronic devices.