QPHT-graphene: A new two-dimensional metallic carbon allotrope

Palgraphyne: A Promising 2D Carbon Dirac Semimetal with Strong Mechanical and Electronic Anisotropy

“…From the bonding features of carbon atoms, the proposed 2D carbon allotropes can be roughly classified into three types. The first one is the plane graphene‐like allotropes (e.g., phagraphene, H‐net, biphenylene carbon, and “QPHT” graphene composed of quadrangular, pentagonal, and hexagonal rings and large tetradecagonal pores), in which all of the atoms are sp 2 hybridized. The second type is the plane graphyne‐like phases (e.g., δ‐,, α‐, β‐graphyne, 6,6,12‐graphyne, and cp‐graphyne), in which there are sp‐hybridized C—C atomic linkages in addition to sp 2 ‐hybridized C atoms.…”

“…Following the discovery of graphene in 2004, more and more 2D carbon allotropes with various properties have been proposed in theory. For their predictions, there exist three typical approaches: 1) introducing various defects in graphene, e.g., the metallic dimerite can be obtained from graphene by inserting Stone–Thrower–Wales defects; 2) unbiased structural searching based on different advanced methods, e.g., the CALYPSO algorithm has been employed to search various Dirac carbon allotropes; 3) exfoliating from the corresponding 3D layered structures, e.g., ph‐graphene has been cleaved from the solid C 36 quasi‐2D membrane.…”

Three-dimensional carbon nanotube networks from beta zeolite templates: Thermal stability and mechanical properties

“…The search for new carbon-based nanostructures remains a very active research area [1][2][3][4][5][6][7][8][9][10]. These novel structures can have different dimensionalities (0D, 1D, 2D, and 3D) and exhibit a wide range of electrical, thermal, and mechanical properties [11,12].…”

PCF-Graphene: A 2D sp2-Hybridized Carbon Allotrope with a Direct Band Gap

“…Graphene has a honeycomb lattice structure with one-atom thickness and exhibits many novel properties such as high electron mobility, , ambipolar effect, Klein tunneling, massless Dirac fermions, and anomalous quantum Hall effect, showing great potential for applications in high-speed electronic, radio frequency logic devices, , thermally and electrically conductive reinforced composites, sensors, and transparent electrodes. , These findings have stimulated tremendous interest in exploring other two-dimensional (2D) carbon structures including phagraphene, T-graphene, octagraphene, penta-graphene, supergraphene, twin graphene, DHP-graphene, Haeckelite, QPHT-graphene, and popgraphene . These theoretically proposed graphene allotropes have many intriguing properties; however, none of them has been experimentally synthesized so far.…”