Studying The Effect Of Doping On Magnetic Properties Of 2D Materials Based On Density Fuctional Theory

New nano-electronic devices have been used everywhere in our daily life,and its application directly affect people's living standards.With the successful synthesis of two-dimensional nano-material such as grapheme,BN,MoS2 in the laboratory,researchers have paid close attention to the related research on the two-dimensional nanomaterials.If the magnetism of these materials can be effectively controlled,it's bound about a greater breakthrough for technological innovation in the field of materials applications,and it will be possible to further design a spin electronic devices,which is more compact,convenient and stable,more functional and efficient.Previous works show that transition metal doping can effectively introduce and control the electronic structure and magnetism of 2D materials,so as to lay a theoretical foundation for the application of two-dimensional materials in spin devices.In order to find out whether other two dimensional materials have similar characteristics,this paper studies transition metal atoms doping and adsorbing in Mo₂ C through the first-principles calculation,hoping to find the general law of adjusting the magnetic properties of two-dimensional materials.We believe that these studies will effectively promote properties of Mo₂ C material,and it will let Mo₂ C play a vital role in the field of spin devices.The main research work and achievements are summarized as follows:1.A systematic study has been carried out to investigate the structure,binding energy and electronic property of transition metal atoms?TMs??including Sc?Ti?V?Cr?Mn?Fe?Co and Ni atom?doped in Mo₂ C.We found that the geometrical property and stability of the Mo₂ C structure are closely related to the site of TMs and the type of TMs.TMs can well form chemical bond with the closely C atoms.Some TMs can lead Mo₂ C to possess magnetism effectively,the magnetic properties of those structures are mainly derived from TMs,and those magnetic value are related to the number of valence electrons belonging to TMs.Therefore,through the doping of different TMs,we can control the electronic structure of Mo₂ C,leading it to be used at many novel fields.2.A systematic study has been carried out to investigate the structure,energy of adsorption and electronic property of transition metal atoms?TMs??including Sc?Ti?V?Cr?Mn?Fe?Co and Ni atom?adsorbed in Mo₂ C.We found that the geometrical property and stability of the Mo₂ C structure are also closely related to the site of TMs and the type of TMs.TMs can well form chemical bond with the closely Mo atoms.Some TMs can lead Mo₂ C to process magnetism effectively.the magnetic properties of those structures are mainly derived from TMs,and those magnetic value are related to the number of valence electrons belonging to TMs.Therefore,through the adsorption of different TMs,we can control the electronic structure of Mo₂ C,leading it to be used at many novel fields.