Molecular dynamics study of xenon on an amorphous Al2O3 surface

Xenon self-diffusion on amorphous Al2O3 surfaces has been studied using molecular dynamics (MD) simulations. The results show that the topology of the amorphous alumina surface has a considerable effect on the mobility of Xe. Adding nanoscale scratches to the surface will both increase the adsorption energies and lower the surface diffusion coefficients. These findings give a possible explanation to the need for unexpectedly thick ALD deposited amorphous Al2O3 films used as gas diffusion barriers on polymeric systems.