Theoretical study for adsorption and migration behavior of atoms/ions on sinusoidal corrugated graphene surface

Abstract

The adsorption and migration behaviors of atoms/ions on the surface of infinite single-layer graphene are studied with the influence of surface corrugation taken into consideration. Based on Lennard-Jones (L-J) potential and Fourier expansion, the analytical expressions of the interaction potential and force between a single atom/ion and sinusoidal corrugated graphene are derived. The effects of lattice period, chirality, wavelength and amplitude of surface sinusoidal ripples on the mechanical behaviors of atom/ion adsorption and migration on graphene surface are analyzed. The interaction potential and force between the adsorbed atom/ion and graphene are found to be periodic when the lattice period of graphene and the wavelength of surface sinusoidal ripples meet a certain coupling relationship. Moreover, the periods of interaction potential and force, equilibrium position and diffusion barrier of the adsorbed atom/ion on the graphene surface can be regulated by changing the wavelength and amplitude of the sinusoidal ripples. Taking lithium-ion (Li1+) as an example, by changing the wavelength of the sinusoidal ripples, the equilibrium sites of a lithium-ion on the surface of graphene can be readjusted, and the magnitude and amount of the energy barriers that it gets over can be regulated when the lithium-ion moves along the surface of graphene. What is more, the amplitude of the sinusoidal ripples can significantly influence the tangential force exerted by the graphene on the moving lithium-ion. Finally, it is found that the migration of an adsorbed atom/ion on the surface of sinusoidal corrugated graphene is also dependent on the chirality of graphene. The magnitude and period of the energy barrier and tangential force are both different when a lithium-ion migrates on the graphene surface in its different chiral directions. This research may be helpful to lithium-ion batteries, monoatomic device design, and atoms/ions screening.