The Magnetic Properties Of Hydrogenated Penta-graphene By Theoretical Study

In recent years,magnetic materials have been widely used in all kinds of electronic device production,machinery manufacturing,transportation,and our daily life,which become the basis of functional materials in a high-tech industry.With the development of science and technology,a variety of electronic devices and electrical components will be moved towards smaller,lighter,thinner and multi-functional direction,thus the requirements of size,performance of magnetic material are getting higher and higher.In order to meet the development of high-tech and the needs of emerging markets,the study of new magnetic materials,especially the study of nano-magnetic materials will become one of the key researches of magnetic materials.In 2015,Professor Wang et.al simulated a new graphene structure-penta-graphene by computer fitting.It may be superior to graphene in some fields on account of its properties such as mechanical stability,high strength and the high temperature resistance.The pure graphene was not magnetically,but it can be magnetized by making the structure of graphene adsorb atoms,create vacancies and topological defects.Thus,we can study the magnetic properties of penta-graphene with the same method.In this paper,we first made four penta-graphene 1�1,2�2,3�3 and 4�4 cell structures which are absorbed by hydrogen atom,and got the corresponding stable adsorption structures.Then,we calculated the magnetic properties of the hydrogened penta-graphene structures by the First Principle Calculation and the Density Functional Theory.The results show that the 1�1 hydrogened penta-graphene structures was nonmagnetic(the nonmagnetic adsorption structure of hydrogened penta-graphene),and the 2�2,3�3 and 4�4 hydrogened penta-graphene structures have induced magnetism,the magnetic moments of the three structures are all 0.557 ?B/cell.And the main sources of magnetic moments were the p state electrons of C2 atoms in the penta-graphene structure by analyzing the density of state curves of the 2�2,3�3 and 4�4 structures of the hydrogened penta-graphene.In addition,by increasing the adsorption height of the hydrogen atoms in the 1�1 unit cell structure of the hydrogened penta-graphene,it was found that the new 1�1 hydrogened penta-graphene structure showed magnetism(the magnetic adsorption structure of hydrogened penta-graphene),and the magnetic moment was 0.551 ?B/cell.By analyzing the density of state curve,we can find that the main source of magnetic moments for the magnetic adsorption structure of hydrogened penta-graphene was also the p state electron of C2 atoms in the penta-graphene structure.Then,we studied the density of charge distribution of these five structures,respectively.It was found that the charge in the penta-graphene was redistributed when the hydrogen atoms were adsorbed on the penta-graphene structure,in which the H atoms and the C1 atoms got a lot of charge between the atoms,while the C2 atoms got relatively less charge.The two 1�1 hydrogened penta-graphene structures can be regarded as a nano-magnetic switch,and the entire adsorption structure showed the magnetism when increasing the adsorption height of hydrogen atoms,while it showed no magnetic property when decreasing the adsorption height of hydrogen atoms.Besides,the magnetic adsorption structure of 1�1 hydrogened penta-graphene can also be called the smallest structural of hydrogened penta-graphene structures which could produce the largest magnetic moment.Finally,we calculated the potential barrier between the two structures of the 1�1 hydrogened penta-graphene,the results showed that the transition between the two structures required only a small energy.Thus it can be seen that the nano-magnetic switch may be realized,and it can be widely used in aerospace and military and other fields.