Graphene-like two-dimensional ionic boron with double dirac cones at ambient condition


Autoria(s): Ma, Fengxian; Jiao, Yalong; Gao, Guoping; Gu, YuanTong; Bilic, Ante; Chen, Zhongfang; Du, Aijun
Data(s)

2016

Resumo

Recently, partially ionic boron (γ-B28) has been predicted and observed in pure boron, in bulk phase and controlled by pressure [Nature, 457 (2009) 863]. By using ab initio evolutionary structure search, we report the prediction of ionic boron at a reduced dimension and ambient pressure, namely, the two-dimensional (2D) ionic boron. This 2D boron structure consists of graphene-like plane and B2 atom pairs, with the P6/mmm space group and 6 atoms in the unit cell, and has lower energy than the previously reported α-sheet structure and its analogues. Its dynamical and thermal stability are confirmed by the phonon-spectrum and ab initio molecular dynamics simulation. In addition, this phase exhibits double Dirac cones with massless Dirac fermions due to the significant charge transfer between the graphene-like plane and B2 pair that enhances the energetic stability of the P6/mmm boron. A Fermi velocity (vf) as high as 2.3 x 106 m/s, which is even higher than that of graphene (0.82 x 106 m/s), is predicted for the P6/mmm boron. The present work is the first report of the 2D ionic boron at atmospheric pressure. The unique electronic structure renders the 2D ionic boron a promising 2D material for applications in nanoelectronics.

Formato

application/pdf

Identificador

http://eprints.qut.edu.au/95300/

Publicador

American Chemical Society

Relação

http://eprints.qut.edu.au/95300/3/95300.pdf

DOI:10.1021/acs.nanolett.5b05292

Ma, Fengxian, Jiao, Yalong, Gao, Guoping, Gu, YuanTong, Bilic, Ante, Chen, Zhongfang, & Du, Aijun (2016) Graphene-like two-dimensional ionic boron with double dirac cones at ambient condition. Nano Letters. (In Press)

Direitos

Copyright 2016 American Chemical Society

Fonte

School of Chemistry, Physics & Mechanical Engineering; Science & Engineering Faculty

Palavras-Chave #2D boron #Dirac cone #graphene analogous #density functional theory
Tipo

Journal Article