Stochastic Nonlinear Dynamic Characteristics and Safe Basin of Li-doped Graphene-absorbing Hydrogen Atoms Subjected to Thermal Perturbation

摘要

Thermal perturbation may induce complex motion of grapheme-absorbing hydrogen atoms, which causes the escape of adsorbed hydrogen atoms. The area where hydrogen atoms cannot escape from graphene is defined as safe basin. In this article, stochastic nonlinear dynamic characteristics and safe basin of Li-doped graphene-absorbing hydrogen atoms subjected to thermal perturbation are studied. The interaction of hydrogen atoms to graphene is regarded as white noise. The nonlinear dynamic model of Li-doped graphene impacted by hydrogen atoms is developed, in which the effect of Ni irons on the graphene stiffness is considered. The conditions of noise-induced chaotic response are obtained using stochastic Melnikov integral method. In addition, the fractal boundary of the system safe basin is provided. Finally, the reliability function of the system is solved. Theoretical analysis and numerical simulation show that the boundary of safe basin has fractal characteristics, which means chaos induced by noise; the area of safe basin decreases when the intensity of the noise increases; the inhomogeneity of graphene stiffness can affect the system safe basin, which decides the actual hydrogen storage capacity of graphene. The results of this paper are helpful to the graphene application in hydrogen storage fields.