Encapsulation of volatile fission products in a two-dimensional dicalcium nitride electride

The efficient capture of volatile fission products released during spent fuel reprocessing is a crucial concern for the nuclear community. Here, we apply the density functional theory to examine the efficacy of a two-dimensional dicalcium nitride electride (Ca2N:e) to encapsulate volatile fission products. Encapsulation is endoergic for Kr, Xe, Rb, and Cs meaning that they are not encapsulated. Conversely, strong encapsulation is exhibited for Br, I, and Te with respect to their atoms and dimers as reference states. The preference for Br, I, and Te encapsulation is a consequence of charge transfer from Ca2N:e to form encapsulated anions. This makes the electride a promising material for the selective trapping of volatile Br, I, and Te.