Structural, mechanical, and electronic properties of single graphyne layers based on a 2D biphenylene network

TL;DR

This paper investigates a novel graphyne structure based on biphenylene monolayer, revealing its stability, highly localized spin-polarized states, and tunable anisotropic electronic properties influenced by structural details.

Contribution

It introduces a new biphenylene-based graphyne system with unique electronic and magnetic properties, expanding the understanding of 2D carbon allotropes.

Findings

The system exhibits highly localized, spin-polarized semiconducting states.

Structural details directly affect the electronic anisotropy.

Tuning acetylenic chain size modulates frontier state symmetry.

Abstract

Graphene is a promising material for the development of applications in nanoelectronic devices, but the lack of a band gap necessitates the search for ways to tune its electronic properties. In addition to doping, defects, and nanoribbons, a more radical alternative is the development of 2D forms with structures that are in clear departure from the honeycomb lattice, such as graphynes, with the distinctive property of involving carbon atoms with both hybridizations sp and sp2. The density and details of how the acetylenic links are distributed allow for a variety of electronic signatures. Here we propose a graphyne system based on the recently synthesized biphenylene monolayer. We demonstrate that this system features highly localized states with a spin-polarized semiconducting configuration. We study its stability and show that the system's structural details directly influence its highly anisotropic electronic properties. Finally, we show that the symmetry of the frontier states can be further tuned by modulating the size of the acetylenic chains forming the system.