Effect of Elasticity of the MoS2 Surface on Li Atom Bouncing and Migration: Mechanism from Ab Initio Molecular Dynamic Investigations

 

Born–Oppenheimer molecular dynamics (BOMD) has been carried out to investigate the evolution of Li atom trapping on the MoS2 surface. A single Li atom is fired with an initial kinetic energy level (0.2 or 2.0 eV) and various targeting factors x, which determines the collision angle. After getting trapped, Li is observed to bounce elastically and glide on the MoS2 surface thanks to the “breathing” vibration of MoS2. Both firing energy and targeting factor x are shown to have a significant effect on the trapping and gliding processes. It is found that a higher value of targeting factor x (≥0.6) and initial firing energy (2.0 eV) enhances Li migration on the MoS2 surface. Also, analysis from electronic structure calculations of six representative Li–MoS2 interacting configurations suggests that there is ionic interaction and partial charge transfer between the absorbed Li atom and MoS2 monolayer during the bouncing and migration process. The HSE calculations for those structures unveils the metallization of MoS2 due to Li attachment.