Adsorption properties of a single uranium atom adsorbed on perfect and defective graphene

Based on the density-function theory, we have systematically investigated the adsorption of a single uranium (U) atom on perfect and defective graphene. We find that U atom is most likely to stay on the hollow site of perfect graphene. The energy barrier for migrating a U atom from one hollow site to another hollow site is 454 meV, which indicates the adsorption is stable at room temperature. Moreover, U atom on defective graphene sheet is much more stable than that on pure graphene due to the formation of strong chemical bond. The adsorption energy is as large as 5.08 similar to 9.37 eV. We also find that all adsorption systems are spin-polarized and their corresponding magnetic moment are in the range of 1.53 similar to 5.07 mu(B). The strong adsorption and large magnetic moments endow these systems with potential applications in the collection for U atoms, spintronic devices and catalytic materials.