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 Li, Na, and 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.

Keywords

• 2D materials
• MXenes
• DFT
• Y2C monolayers
• Ion batteries