Structural and Electronic Properties ofTGraphene: A Two-Dimensional Carbon Allotrope with Tetrarings

Abstract

T graphene, a two-dimensional carbon allotrope with tetrarings, is investigated by first-principles calculations. We demonstrate that buckled T graphene has Dirac-like fermions and a high Fermi velocity similar to graphene even though it has nonequivalent bonds and possesses no hexagonal honeycomb structure. New features of the linear dispersions that are different from graphene are revealed. π and π* bands and the two comprising sublattices are the key factors for the emergence of Dirac-like fermions. T graphene and its two types of nanoribbon are expected to possess additional properties over graphene due to its different band structure.

Electronic properties of T graphene-like C–BN sheets: A density functional theory study

“…For instance, two new forms of two-dimensional carbon sheets with tetragonal symmetry (planar and buckled T graphene) have been suggested by Li et al [10]. The T graphene could be considered to be derived from cleaving two adjacent atom layers in bcc C 8 or bct C 4 along (001) [10]. The planar T graphene is ideally two-dimensional sheet with one sublattice in its unit cell.…”

A low-surface energy carbon allotrope: the case for bcc-C6

“…In stark contrast, the (100) thin layers are always metallic independent of N. Such a metallic behavior may originate from the presence of tetrahedral ring, as having been found in planar T-graphene. 27 PBE calculation usually underestimates the band gap of semiconductors. To improve the accuracy, we have calculated the band gaps of the (111) thin layers using a hybrid functional, HSE06: the N = 2 gap increases from 0.02 to 0.6 eV, while the N = 3 gap increases from 2.2 to 3.2 eV.…”

“…Although by in large, few studies on the nanostructures of carbon allotropes have been performed. 27 Recently, other two-dimensional layered structures, such as transition metal dichalcogenide (TMD) attracted much attention. [28][29][30][31] Among the reasons, the TMD exhibits an indirect to direct transition at monolayer thickness.…”

Multiporous carbon allotropes transformed from symmetry-matched carbon nanotubes

“…Besides the well-known diamond, graphite, fullerenes, 1 carbon nanotube(CNTs), 2 amorphous carbon 3 and graphene, 4,5 many other carbon allotropes have been presented in the past decade, including graphdiyne, 6 bcc-C6, 7 HOP graphene, 8 oC32, 9 net W carbon, 10 H-net, 11 GT-8 and CT-12, 12 sp 2 -diamond and cubic-graphite, 13 oP24-I, oP24-II, oP20, oP28, mP16 and mS32, 14 T-carbon, 15 OPG-L and OPG-Z, 16 hexagon-preserving carbon foams, 17 O-carbon, 18 amorphous diamond, 19 R and P carbon, 20 hP3 tI12, and tP12, 21 yne-carbon and tetrayne-carbon, 22 T graphene, 23 oC16, 24 X-carbon and Y-carbon, 25 bct C 4 , 26 carbon schwarzites, 27 K 4 -carbon, 28 T 6 and T 14 -carbon. 29 Their mechanical and electrical properties vary significantly from superhard to soft and from metallic to insulating, which enriches the real applications of carbon materials tremendously.…”