First-principles Study On Adsorption And Doping Of Graphene By Aluminum Atom

The traditional aluminum matrix composites are widely used in civil and military fields because of their light weight,high specific strength and specific rigidity,low coefficient of thermal expansion,easy processing and a series of excellent performance.However,the ordinary aluminum alloy material has been unable to meet the needs of modern industrial high-speed development.In order to obtain a better overall performance of aluminum matrix composites,to find a more appropriate enhancement phase is to improve its performance research focus.The graphene has many excellent physical and chemical properties as an enhanced phase of aluminum matrix composites,which can effectively improve the strength and elastic modulus of aluminum alloy.Based on the first-principles calculation of density functional theory,the electronic structure of aluminum atoms adsorbed on intrinsic graphene and doping graphene and its related properties are studied.Based on the CASTEP module in the Material Studio software,the adsorption of Al atoms on the adsorption sites of the intrinsic graphene at different adsorption sites was studied systematically.The adsorption of Al atoms on the graphene and Al atoms was adsorbed on the four doped graphene The In this paper,we mainly calculate the electronic structure,energy,density,energy band and charge transfer situation.The first chapter mainly introduces the research status of aluminum matrix composites,graphene reinforced aluminum matrix composites at home and abroad,and some preparation methods of graphene reinforced metal matrix composites in the present experiment.The second chapter mainly introduces the development process and principle of the first principle based on density functional theory.Among them,the density functional theory mainly includes Thomas-Fermi model,Hoenberg-Kohn theorem and Kohn-Sham equation.At the same time,we also briefly describe the Castep package we calculated in the simulation software Material Studio.In the third chapter,we use the method mentioned in Chapter 2 to calculate the effect of the adsorption position of single / double aluminum atoms on the electronic structure of graphene.It is found that the best position of single atom adsorption is acupoint and diatomic optimal adsorption For the meta.At the same time,diatomic adsorption of graphene is more stable than monatomic adsorption graphene.The fourth chapter is based on the third chapter,because the two-atom adsorption is more stable than the single-atom adsorption structure,taking into account the increase in the number of adsorbed aluminum atoms,graphene structure changes.It was found that the graphene adsorption system became more and more stable with the increase of coverage(the number of adsorbed Al atoms).While the adsorption of aluminum atoms is physical adsorption.In the fifth chapter,the change of the electronic structure of aluminum atoms adsorbed on the surface of doping graphene(doped atoms: B,N,O,P)is calculated.The results show that aluminum atoms adsorbed on oxygen / phosphorus-graphene system,and the destruction of graphene structure is large.The bond charge is mainly transferred from the orbit of the aluminum atom,and the differential charge distribution is localized from the differential charge density distribution,mainly on the electron orbit between the aluminum atoms and the dopant atoms.Chapter 6 is a summary of the work of this article and a vision for future work.