Hydrogen Adsorption of Back Side of Graphene

TL;DR

This study uses molecular dynamics simulations to investigate how hydrogen atoms interact with the backside of graphene, revealing conditions for adsorption, reflection, and penetration, and how structural changes influence these interactions.

Contribution

It introduces a detailed analysis of backside hydrogen adsorption on graphene, highlighting the role of incident energy and structural modifications in adsorption behavior.

Findings

Backside adsorption occurs when hydrogen energy exceeds the potential barrier.

Adsorption site shifts to the hexagonal hole periphery with increased incident energy.

Expansion of the hexagonal hole reduces the potential barrier, facilitating adsorption.

Abstract

We studied the interaction between a single hydrogen atom and a single graphene using classical molecular dynamics simulation with modified Brenner REBO potential. Three interactions, which are adsorption, reflection, penetration, were observed. Overhang structure appears and creates an adsorption site on the backside of the graphene. It is considered that backside adsorption occurs under the two conditions that an incident hydrogen atom should have incident energy which is larger than the potential barrier of a hexagonal hole of the graphene and that after the hydrogen atom passes through the graphene, it does not keep its kinetic energy to be trapped by the adsorption site. The conditions explained that as the incident energy increased, the incident point of the backside adsorption shifted to the periphery of a hexagonal hole of the graphene in the simulation. Moreover, when a hexagonal hole of the graphene was expanded by the hydrogen atom incidence to the periphery of the hexagonal hole, its potential barrier was reduced.