Oxygen adsorption and diffusion on γ-U(0 0 1) surface: Effect of titanium

Abstract

Titanium (Ti) decoration is considered as a promising strategy for preventing metallic uranium (U) surface from oxidization and corrosion. The O adsorption and diffusion behaviors on the clean and Ti-decorated γ-U(0 0 1) surfaces have been investigated by density functional theory (DFT) calculations in the present work. The preferred sites and stable configurations for O atoms on the surface and in the subsurface have been evaluated. It is found that O atoms tend to adsorb on the surface instead of absorbing in the subsurface. With nudged elastic band method, O atom on Ti-doped surfaces departs from the energetically favored site which there is a higher barrier than it on clean U surface. O and Ti can form a chemical bond of Ti-O, reducing the interaction of U and O, thereby enhancing the corrosion resistance of U surface.