DFT investigations of structural and electronic properties of two-dimensional Y2C and Y2CF2 monolayers

Abstract

We designed Y₂CF₂ monolayers by adding fluorine atoms in place of the anionic electrons in Y₂C monolayers. The density functional theory (DFT) is used to investigate the structural and electronic properties of two-dimensional Y₂C and Y₂CF₂ monolayers. According to the results of calculations, these monolayers are dynamically and thermodynamically stable. The structural and electronic properties of the Y₂CF₂ monolayer exhibit a semimetallic behavior. To study the potential applications of these new two-dimensional electride material, the adsorption and diffusion properties to atoms $\text{Li}$, $\text{Na}$, and $\text{Mg}$ are investigated. Our results indicate that the diffusion barriers of Li, Na, and Mg atoms on the Y₂CF₂ surface are 15.9 eV, 6.8 eV, and 28.6 eV, respectively. Because of their high adsorption energies and low diffusion barriers of metal atoms, Y₂C and Y₂CF₂ monolayers are attractive electride materials for applications of metal-ion batteries. All of the findings contribute to the modification, stabilization, and understanding of two-dimensional electrides, as well as the practical use of their characteristics.