Exploring surface effects in Co doped ZnO nanowires with hybrid-density functional theory

Abstract

In this work, density-functional theory with hybrid functionals is employed to investigate the atomic and electronic structure of bare and hydrogenated Co doped ZnO nanowires. It is found that, in the absence of passivation on the nanowire surface, the cobalt atoms segregate to the surface. On the other hand, under hydrogen passivation, the incorporation of Co is more favorable at inner sites. This suggests that the incorporation of Co in nanostructures has a dependence on the environment and may be facilitated by adsorption of external atoms and relaxation of the wire surface.