A Dirac-semimetal two-dimensional BeN4: Thickness-dependent electronic and optical properties

Abstract

Motivated by the recent experimental realization of a two-dimensional (2D) BeN4 monolayer, in this study we investigate the structural, dynamical, electronic, and optical properties of a monolayer and few-layer BeN4 using first-principles calculations. The calculated phonon band dispersion reveals the dynamical stability of a free-standing BeN4 layer, while the cohesive energy indicates the energetic feasibility of the material. Electronic band dispersions show that monolayer BeN4 is a semi-metal whose conduction and valence bands touch each other at the Σ point. Our results reveal that increasing the layer number from single to six-layers tunes the electronic nature of BeN4. While monolayer and bilayer structures display a semi-metallic behavior, structures thicker than that of three-layers exhibit a metallic nature. Moreover, the optical parameters calculated for monolayer and bilayer structures reveal that the bilayer can absorb visible light in the ultraviolet and visible regions better than the monolayer structure. Our study investigates the electronic properties of Dirac-semimetal BeN4 that can be an important candidate for applications in nanoelectronic and optoelectronic.

Thermal Properties of 2D Dirac Materials MN4 (M = Be and Mg): A First-Principles Study

“…These data are consistent with that from previous work. 19 , 30 Besides, the electron localization functions (ELF) of two monolayers are calculated to further analyze the bonding nature. The ELF results with an isovalue of 0.7 are shown in Figure 2 and are similar to other DFT results.…”

Li-doped beryllonitrene for enhanced carbon dioxide capture

“…Beryllonitrene is similar to the previously stated two-dimensional materials in that it’s structure is close to a honeycomb structure, and it has a hexagonal unit cell. 43 Each unit cell consists of one beryllium atom and four nitrogen atoms, so the material is mostly composed of nitrogen. 43 Like in boron nitride, these nitrogens could act as potential carbon dioxide adsorption sites.…”

“… 43 Each unit cell consists of one beryllium atom and four nitrogen atoms, so the material is mostly composed of nitrogen. 43 Like in boron nitride, these nitrogens could act as potential carbon dioxide adsorption sites. 19 Beryllonitrene has been shown to be both dynamically and thermodynamically stable.…”

“… 19 Beryllonitrene has been shown to be both dynamically and thermodynamically stable. 42 The monolayer exhibits semimetallic behavior 43 and has a large surface area, similar to other two-dimensional materials, making it a good candidate for CO 2 adsorption. Due to the unique properties and lack of research for beryllonitrene, it is important to investigate the potential of beryllonitrene for CO 2 capture.…”

Biphenylene monolayer as a two-dimensional nonbenzenoid carbon allotrope: A first-principles study

“…Among these forms of carbon allotropes, twodimensional (2D) graphene and its like have been extensively studied theoretically and experimentally. [16][17][18][19][20] In addition, graphene has piqued the curiosity of scientists in a wide range of domains. To be more specific, this 2D material is a single, thin sheet of carbon atoms organized in a hexagonal honeycomb pattern that is one atom thick.…”