A First-principles Study Of Anode Materials For Alkali Metal Ion Batteries

Computational chemistry,as a new subject,has been widely paid attention to in recent years.Its formation and development are closely related to the progress of modern computer technology,and it is gradually transformed into a relatively independent field of scientific research.Computational chemistry has been widely used in materials science and other fields.In addition,as one of the most versatile energy storage methods,the exploration of electrode materials for alkali metal ion batteries has never stopped.Therefore,this paper combines computational chemistry with energy storage materials,and attempts to design and simulate ion battery anode materials.It mainly carries out the following two works.1.Phonon spectra,(Ab initio Molecular Dynamics)AIMD simulations and elastic constants of graphene-like BC₃monolayers are studied in this paper.Our results show that the graphene-like BC₃monollayer has good structural stability with a maximum theoretical potassium storage capacity up to 1145 m Ah/g and a corresponding open-circuit voltage of0.66 V.Since potassium atoms can be effectively adsorbed at the H-CC position with the most favorable energy and the charge transfer is obvious,the adsorbed graphene-like BC₃monolayer changes from semiconductor to metal,which is very beneficial to the utilization of the electrode.In addition,the diffusion barrier of potassium atom in graphene-like BC₃monolayer is as low as 0.12 e V,while the diffusion barrier of lithium atom is relatively large(0.46 e V).In addition,the tensile strain applied on graphene-like BC₃monolayer has little effect on the adsorption and diffusion properties of lithium,sodium and potassium atoms.2.In this paper,the types of graphene Al P single-layer structure study,based on first principles,the structure of a kind of graphene Al P monolayer electronic stability of structure,thermodynamics and kinetics,diffusion barrier,theoretical capacity is discussed,and the average voltage research shows that alkali metal atoms in the class graphene Al P Pdown is the most stable adsorption sites on single layer.The minimum diffusion barrier is0.26 e V(Li),and the maximum theoretical capacity is 1103 m Ah/g(Na/K).It is a promising anode material for ion batteries.