TY - JOUR
T1 - Face-centered cubic carbon as a fourth basic carbon allotrope with properties of intrinsic semiconductors and ultra-wide bandgap
AU - Konyashin, Igor
AU - Muydinov, Ruslan
AU - Cammarata, Antonio
AU - Bondarev, Andrey
AU - Rusu, Marin
AU - Koliogiorgos, Athanasios
AU - Polcar, Tomáš
AU - Twitchen, Daniel
AU - Colard, Pierre Olivier
AU - Szyszka, Bernd
AU - Palmer, Nicola
N1 - Publisher Copyright:
© The Author(s) 2024.
PY - 2024/12
Y1 - 2024/12
N2 - Carbon is considered to exist in three basic forms: diamond, graphite/graphene/fullerenes, and carbyne, which differ in a type of atomic orbitals hybridization. Since several decades the existence of the fourth basic carbon allotropic form with the face-centered cubic (fcc) crystal lattice has been a matter of discussion despite clear evidence for its laboratory synthesis and presence in nature. Here, we obtain this carbon allotrope in form of epitaxial films on diamond in a quantity sufficient to perform their comprehensive studies. The carbon material has an fcc crystal structure, shows a negative electron affinity, and is characterized by a peculiar hybridization of the valence atomic orbitals. Its bandgap (~6 eV) is typical for insulators, whereas the noticeable electrical conductivity (~0.1 S m−1) increases with temperature, which is typical for semiconductors. Ab initio calculations explain this apparent contradiction by noncovalent sharing p-electrons present in the uncommon valence band structure comprising an intraband gap. This carbon allotrope can create a new pathway to ‘carbon electronics’ as the first intrinsic semiconductor with an ultra-wide bandgap.
AB - Carbon is considered to exist in three basic forms: diamond, graphite/graphene/fullerenes, and carbyne, which differ in a type of atomic orbitals hybridization. Since several decades the existence of the fourth basic carbon allotropic form with the face-centered cubic (fcc) crystal lattice has been a matter of discussion despite clear evidence for its laboratory synthesis and presence in nature. Here, we obtain this carbon allotrope in form of epitaxial films on diamond in a quantity sufficient to perform their comprehensive studies. The carbon material has an fcc crystal structure, shows a negative electron affinity, and is characterized by a peculiar hybridization of the valence atomic orbitals. Its bandgap (~6 eV) is typical for insulators, whereas the noticeable electrical conductivity (~0.1 S m−1) increases with temperature, which is typical for semiconductors. Ab initio calculations explain this apparent contradiction by noncovalent sharing p-electrons present in the uncommon valence band structure comprising an intraband gap. This carbon allotrope can create a new pathway to ‘carbon electronics’ as the first intrinsic semiconductor with an ultra-wide bandgap.
UR - http://www.scopus.com/inward/record.url?scp=85197300877&partnerID=8YFLogxK
U2 - 10.1038/s43246-024-00547-8
DO - 10.1038/s43246-024-00547-8
M3 - Article
AN - SCOPUS:85197300877
SN - 2662-4443
VL - 5
JO - Communications Materials
JF - Communications Materials
IS - 1
M1 - 115
ER -