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

A Bafekry; M Faraji; M M Fadlallah; H R Jappor; S Karbasizadeh; M Ghergherehchi; D Gogova

doi:10.1088/1361-648X/ac2a7b

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

J Phys Condens Matter. 2021 Oct 27;34(1). doi: 10.1088/1361-648X/ac2a7b.

Authors

A Bafekry¹, M Faraji², M M Fadlallah³, H R Jappor⁴, S Karbasizadeh⁵, M Ghergherehchi⁶, D Gogova⁷

Affiliations

¹ Department of Radiation Application, Shahid Beheshti University, 19839 69411 Tehran, Iran.
² Micro and Nanotechnology Graduate Program, TOBB University of Economics and Technology, Sogutozu Caddesi No 43 Sogutozu, 06560, Ankara, Turkey.
³ Department of Physics, Faculty of Science, Benha University, 13518 Benha, Egypt.
⁴ Department of Physics, College of Education for Pure Sciences, University of Babylon, Hilla, Iraq.
⁵ Department of Physics, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
⁶ Department of Electrical and Computer Engineering, Sungkyunkwan University, 16419 Suwon, Republic of Korea.
⁷ Department of Physics, Chemistry and Biology, Linkoping University, Sweden.

PMID: 34571501
DOI: 10.1088/1361-648X/ac2a7b

Abstract

In a very recent accomplishment, the two-dimensional form of biphenylene network (BPN) has been fabricated. Motivated by this exciting experimental result on 2D layered BPN structure, herein we perform detailed density-functional theory-based first-principles calculations, in order to gain insight into the structural, mechanical, electronic and optical properties of this promising nanomaterial. Our theoretical results reveal the BPN structure is constructed from three rings of tetragon, hexagon and octagon, meanwhile the electron localization function shows very strong bonds between the C atoms in the structure. The dynamical stability of BPN is verified via the phonon band dispersion calculations. The mechanical properties reveal the brittle behavior of BPN monolayer. The Young's modulus has been computed as 0.1 TPa, which is smaller than the corresponding value of graphene, while the Poisson's ratio determined to be 0.26 is larger than that of graphene. The band structure is evaluated to show the electronic features of the material; determining the BPN monolayer as metallic with a band gap of zero. The optical properties (real and imaginary parts of the dielectric function, and the absorption spectrum) uncover BPN as an insulator along thezzdirection, while owning metallic properties inxxandyydirections. We anticipate that our discoveries will pave the way to the successful implementation of this 2D allotrope of carbon in advanced nanoelectronics.

Keywords: biphenylene monolayer; carbon allotrope; density functional theory; first-principles study; two-dimensional nonbenzenoid.