Prediction of a new two-dimensional metallic carbon allotrope

• Published in: Physical chemistry chemical physics : PCCP 2013-02, Vol.15 (6), p.2024-2030
• Main Authors: WANG, Xin-Quan, LI, Han-Dong, WANG, Jian-Tao
• Format: Article
• Language: English
• Subjects: Allotropy; Carbon; Chemistry; Colloidal state and disperse state; Exact sciences and technology; Fermi surfaces; General and physical chemistry; Nanoelectronics; Nanostructure; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Ribbons; Semiconductivity; Two dimensional
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c2cp43070c

By means of the first-principles calculations, we predict a new metallic two-dimensional carbon allotrope named net W with Cmmm (D(2h)(19)) symmetry. This new carbon phase consists of squares C(4), hexagons C(6), and octagons C(8), its dynamical stability is validated based on phonon-mode analysis and it is energetically more favored over previously proposed two-dimensional carbon forms such as net C, planar C(4), biphenylene, graphyne, and the recently prepared graphdiyne. On the other hand, we find that net W possesses strong metallicity due to its rather large density of states across the Fermi level contributed by the carbon p(z) orbital. Through first-principles molecular dynamics simulations, we theoretically demonstrate that selective dehydrogenation of the parallel-laid narrowest angular polycyclic aromatic hydrocarbons (4-AGNRs) would lead to a spontaneous interconversion to such a net W carbon phase, the possible synthetic routes are also addressed. Of particular interest, semiconductivity could be introduced when a net W carbon sheet is cut into ribbons of certain widths. Our work shows that the net W carbon sheet and its nanoribbons have great potential for future nanoelectronics.