Theoretical study of the interaction between metallic fission products and defective graphite

Abstract

The adsorption and diffusion behaviors of the metallic fission products of Cs, Sr, Ag on the defective graphite surface with double vacancy and Stone–Wales defect are theoretically studied by using density functional theory. Our results show that the Cs, Sr and Ag adatoms are adsorbed preferably at the defect areas of graphite surface. Electronic structure analysis indicates that the defects enhance the adsorption of metallic fission products. Further study on the diffusion properties also proves that the adatoms prefer to diffuse toward the defective area. These processes can readily occur due to zero or ignorable diffusion energy barriers of different kinds of point defects, indicating that point defects can serve as the trap sites for the metallic fission products.