Speaker
Description
Besides the three basic forms of carbon, i.e. diamond, graphite/graphene and fullerene, a fourth carbon allotrope has been identified. We obtained this carbon allotrope in form of epitaxial films on diamond in a quantity sufficient to perform their comprehensive studies, and provided clear evidence for its unique crystal and electronic structure. Its band gap was found to be typical for insulators, whereas the material has a noticeable electrical conductivity, and its temperature dependence is the typical one for semiconductors. In this work, we present the physical insights we obtained on the electronic properties of such carbon allotrope by means of ab initio simulations. The quantum mechanical results provide a possible explanation on the apparent contradiction between the large bandgap and the conductivity features, by pointing at noncovalent electron sharing of p-electrons of neighbouring carbon atoms. The individuated carbon allotrope can create a new pathway to ‘carbon electronics’, as it is the first carbon material having properties of intrinsic semiconductors.
This work was co-funded by the European Union under the project “Robotics and advanced industrial production” (reg. no. CZ.02.01.01/00/22_008/0004590). This work has also been done with the support of the Ministry of Education, Youth and Sports of the Czech Republic through the e-INFRA CZ (ID:90254) and access to the computational infrastructure of the OP VVV-funded project CZ.02.1.01/0.0/0.0/16_019/0000765 “Research Center for Informatics”.
References
[1] I. Konyashin, R. Muydinov, A. Cammarata et al. “Face-centered cubic carbon as a fourth basic carbon allotrope with properties of intrinsic semiconductors and ultra-wide bandgap”, Communications Materials 5, 115 (2024).
