The Manipulation Of Magnetic Properties And Oxygen Reduction Reaction On Two Dimensional Materials By Doping And Strain

The two-dimensional nanomaterials have received a lot of attentions from researchers because of their incomparable physical and chemical performances,owing to the unique layered structure.Graphene and molybdenum disulfide,as the typical two-dimensional materials,have been studied extensively due to their easy preparation,adjustable structure and composition.However,the zero bandgap of graphene and non-magnetic property of molybdenum disulfide greatly hinder their applications in the field of electrocatalysis and magnetic electronic devices,respectively.By introducing straining and single-atom doping,the above limits can be solved.While,to understand the relative physical mechanism at atomic scale is still facing experimental challenges and theoretical deficiencies.With the rapid development of information technology,the method of first-principle calculation becomes mature.Based on first-principle calculation,the physical and chemistry properties of material can be reasonably predicted by giving some basic parameters of the material(m₀,e,h,c,k _B).Compared with experiments,it greatly saves the experimental cost and guide the experimental research.Based on this,this paper utilized first-principle calculation to systematically study the strained and doped graphene and molybdenum disulfide,the catalytic physical mechanism and magnetic properties are explored,respectively.The specific work contents are as follows:(1)Electrocatalytic reactions on strained and single-atom doped two-dimensional materials:By using first-principle calculation,the synergistic catalytic mechanism of the oxygen reduction reaction on local structure of single-atom Pt doped graphene was studied.Our results reveal the synergistic catalytic mechanism between strain and Pt doping in graphene.Compared with Pt-doped graphene,the synergistic effect of strain and Pt doping can effectively improve the catalytic performance of the oxygen reduction reaction.It was found that Pt doping makes the electron state near the Fermi level of the C atom at adsorption site change from unoccupied to occupied,leading to the improvement of the electrical conductivity of the material.The conductivity can be further improved by introducing strain.So strain and Pt doping can effectively regulate the oxygen reduction capacity of graphene,providing a new solution for the exploration of efficient and inexpensive electrocatalysts.(2)The magnetic properties of strained and single-atom doped two-dimensional materials:we have demonstrated that single-metallic-atom doping can turn the magnetic properties of monolayer molybdenum disulfide.The magnetic properties can be further regulated by introduction of strain.In addition,it is found that the electrons transfer and spin density properties are both consistent with the strain effect on the magnetism.Therefore,the magnetic properties of monolayer molybdenum disulfide can be efficiently tuned by strain and single-metallic-atom doping.Our research will be helpful for the future design and development of magnetic electronic devices.