Ultrahigh stiffness and anisotropic Dirac cones in BeN₄ and MgN₄ monolayers

a first-principles study

authored by

B. Mortazavi, F. Shojaei, X. Zhuang

Abstract

Beryllium polynitrides, (BeN₄) is a novel layered material, which has been most recently fabricated under high pressure (Phys. Rev. Lett. 126 (2021), 175501). As a new class of two-dimensional (2D) materials, in this work, we conduct first-principles calculations to examine the stability and explore the electronic nature of MN₄ (M = Be, Mg, Ir, Rh, Ni, Cu, Au, Pd, and Pt) monolayers. Acquired results confirm the dynamical and thermal stability of BeN₄, MgN₄, IrN₄, PtN₄, and RhN₄ monolayers. Interestingly, BeN₄ and MgN₄ monolayers are found to show anisotropic Dirac cones in their electronic structure. Although PtN₄ monolayer is predicted to be a narrow bandgap semiconductor, IrN₄ and RhN₄ monolayers are found to be metallic systems. We also elaborately explore the effects of the number of atomic layers on the electronic features of BeN₄ nanosheets, which reveal highly appealing physics. Our results highlight that BeN₄ nanosheet yield ultrahigh elastic modulus and mechanical strength, outperforming all other carbon-free 2D materials. Notably, RhN₄ nanosheet is predicted to yield high capacities of 562, 450, and 900 mAh/g for Li, Na, and Ca ions storages, respectively. This study provides a comprehensive understanding of the intrinsic properties of MN₄ nanosheets and highlights their outstanding physics.

Organisation(s)

Institute of Photonics
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines

External Organisation(s)

Persian Gulf University
Tongji University

Type

Article

Journal

Materials Today Nano

Volume

15

Publication date

08.2021

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials, Biomaterials, Condensed Matter Physics, Materials Chemistry

Electronic version(s)

https://doi.org/10.48550/arXiv.2105.09733 (Access: Open)
https://doi.org/10.1016/j.mtnano.2021.100125 (Access: Closed)