Barrier effect of oxide on Cu permeation on Be surface

Abstract

Cu–doped–Be capsule has become the international focus of ignition target design and preparation. The interaction between Be and dopants plays an important role in performances of a capsule. In this study, the barrier effect of oxide on Cu permeation on Be slab is studied using ab initio simulations based on van der Waals density-functional theory. We focus on the Cu permeation on both partial and perfect BeO slabs and construct two typical surface structures for the perfect BeO slab with Be-terminated and O-terminated, respectively. The results show that the diffusion of Cu atoms in Be is inhomogeneous and preferentially along the radial direction. We find that the BeO has a blocking effect on Cu atoms diffusion, and the disordered amorphous-like BeO can better impede the inhomogeneous diffusion than the perfect BeO. Furthermore, Cu atoms diffuse with more difficulty on a Be-terminated surface than on an O-terminated surface.