Hexagon Preserving Carbon Nanofoams

Abstract

Carbon foams are hypothetical carbon allotropes that contain graphite-like (sp 2 carbon) segments, connected by sp 3 carbon atoms, resulting in porous structures. In this work the DFTB (Density Functional based Tight-Binding) method with periodic boundary conditions (PBC) was employed to study energetics, the stability and electronic properties of this unusual class of carbon systems. Concerning the most stable phases of carbon (graphite and diamond), foams show high structural stability at very low mass density. The electronic band structure and electronic DOS (density of states) of foams indicate a similar size dependence as carbon nanotubes. The calculated bulk moduli are in the range between that of graphite (5.5 GPa) and diamond (514 GPa). These structures may represent novel stable carbon modifications with sp 2 +sp 3 hybridization.

Formation of Nanofoam carbon and re-emergence of Superconductivity in compressed CaC6

“…From supplementary Table S2, it can be seen that sp 2 -sp 2 bond length in carbon foam is shorter than that in graphite, again indicating its stronger rigidity, which differs from previous reported carbon foam 27,29 . The size of nanoporous is often measured by its border length.…”

“…There are three types of covalent bonds, sp 2 - sp 2 , sp 2 - sp 3 , and sp 3 - sp 3 and five types of bond angles, sp 2 - sp 2 - sp 2 , sp 2 - sp 3 - sp 2 , sp 2 - sp 3 - sp 3 , sp 3 - sp 2 - sp 3 , and sp 3 - sp 3 - sp 3 , as presented in Table supplementary S2, which leads to non-hexagonal cross-section at junction. From supplementary Table S2, it can be seen that sp 2 - sp 2 bond length in carbon foam is shorter than that in graphite, again indicating its stronger rigidity, which differs from previous reported carbon foam2729. The size of nanoporous is often measured by its border length.…”

“…Carbon nanoporous structure is very important because of its potential applications in many fields, such as H 2 absorption, nanodevices, supercapacitors and lithium ion batteries, as well as chemical and bio-sensors. Structurally, the carbon foam, a three-dimensional porous including both sp 2 and sp 3 hybridized atoms, can be thought of as assembled from graphene planes interconnected rigidly with one another at a specific angle, forming a linear chain of sp 3 bonded atoms along the junction 27 . Previously, supposed hybrid carbon foam structures with a mixed sp 2 / sp 3 bonding character 28 29 have received much less attention for lack of direct experimental observation.…”

Sintesis Carbon Nanofoam dan Karakteristiknya

“…Carbon nanofoam (CNF) 0,007 (Ola et al, 2019) Karbon amorf 1,8 -2,1 (Altowyan et al, 2021) Material 3D CNF disebut juga sebagai karbon honeycombs dapat dianggap sebagai struktur grafit dengan peningkatan jarak interlayer yang besar (Zhang et al, 2019a). Pola tepi yang terbuka pada membuat material ini memiliki 2 jenis struktur yang dapat terbentuk yaitu struktur foam zigzag dan armchair, dalam analogi dengan nomenklatur karbon nanotube (Seifert et al, 2011). Kuc dan Seifert (2006), menyatakan bahwa jenis CNF sebagai zigzag (n,m) dan armchair (n,m).…”

A review of the recent trend in the synthesis of carbon nanomaterials derived from oil palm by-product materials

“…~ 1500 [118] ~ 180 [119] 740uS/m [120] ~ 5 to 300 GPA [121] Carbon 3d nanotube network 3D 175 ± 2 m 2 g −1 [122] 0.035 [123] ~ 140 [122] 4.28 ± 0.71 MPa [122] producing CNMs on an extensive scale [133][134][135]. A facile yet homogenous reaction from the microwave method was also introduced in the production of CNMs [136].…”