Energy exchange between discrete breathers in graphane in thermal equilibrium.

Abstract Graphane is a fully hydrogenated graphene which is practically interesting for application in electronics, hydrogen storage and transportation, in nanoscale devices. As it was previously shown, the energy of a discrete breather (nonlinear localized mode) in graphane close to the value of the energy barrier at which the dehydrogenation of graphene occurs. In the present work, molecular dynamics simulation is used to investigate the possibility of energy exchange between discrete breathers in graphane in thermal equilibrium at 400 K and 600 K. In thermally equilibrated graphane, hydrogen atoms are spontaneously excited and can be considered as discrete breathers. Comparison of the kinetic energy per atom as the function of time for the selected hydrogen atoms with their displacements along the z axis showed that there is an energy exchange between the discrete breathers at evaluated temperatures. Hydrogen atom, transmitting its energy to the neighboring atom no longer exists as discrete breather. At high temperatures (600 K) the energy exchange between closely located discrete breathers also take place but strong thermo-oscillations of atoms at high temperatures (above 400 K) considerably affect the process. Highlights • Discrete breathers (DBs) are spontaneously excited in thermally equilibrated graphane. • DBs moves from one excited hydrogen atom to another until the total energy loss. • Thermo-oscillations of atoms at 600 K considerably affect the energy exchange between DBs. • Data on the study of DBs in graphane can be used to hydrogen storage and transportation. [ABSTRACT FROM AUTHOR]