First-principles study of electronic structures of two-dimensional Y₂C electride surfaces

Electrides are attractive ionic compounds in which electrons confined to the narrow interior space in the material act as anions because of their exotic physical and chemical properties such as low work function and efficient electron transfer. In particular, in the case of two-dimensional electride, electrons gather at the interstitial space. In this talk, we report the electronic structure of a two-dimensional Y₂C surface using the first-principles study. We calculate the work function of Y₂C multilayers and analyze how the electronic structure of the material changes when the external electric field is applied. Finally, we discuss what happens to the electronic structure of the Y₂C surface if a Y (or C) atom is missing.