First-principles Study Of The Structure And Properties Of Low-dimensional Functionalized Nanomaterials Based On Density Functional Theory

In recent years,the research on the synthesis and properties of nanomaterials has become a popular research field in domestic and abroad.It is the the research to use various methods to modify the nano materials,which makes the nano materials more suitable for different fields,that has attracted lots of focuses.The study on the properties of modified nano materials will be used to guide the application of experiment and industrialization.In this paper,the structures and properties of carboxyl functionalized carbon nano materials and Germanene-MoS2 heterojunction were studied using the density functional theory to provide reasonable suggestions for experiment and industrial production.Firstly,the carboxyl modified armchair(n,n)and zigzag(n,0)single-walled carbon nanotubes(CNTs)and different types of graphene were studied by M05-2X/6-31G* method.The effect of the position of modification,the diameter,length and chirality of carbon nanotubes on the acid strength was analyzed.The acid strength of the modified carbon nanotubes and graphene were compared.Secondly,the geometry and electronic structure of Ge-MoS2 heterojunction were studied by GGA-PBE method.And the external electric field was added to study the change of the structural properties under the action of electric field.It is found that the heterojunction opens a controllable energy gap under the electric field.Finally,the geometry and electronic structure of amino modified carbon nanotubes were studied at the B97D-6-31G* level.The effect of amino modification on the structure and charge distribution of carbon nanotubes was studied.