Computational insights and the observation of SiC nanograin assembly: towards 2D silicon carbide

Author(s)
Toma Susi, Viera Skákalová, Andreas Mittelberger, Peter Kotrusz, Martin Hulman, Timothy J. Pennycook, Clemens Mangler, Jani Kotakoski, Jannik C. Meyer
Abstract

While an increasing number of two-dimensional (2D) materials, including graphene and silicene, have already been realized, others have only been predicted. An interesting example is the two-dimensional form of silicon carbide (2D-SiC). Here, we present an observation of atomically thin and hexagonally bonded nanosized grains of SiC assembling temporarily in graphene oxide pores during an atomic resolution scanning transmission electron microscopy experiment. Even though these small grains do not fully represent the bulk crystal, simulations indicate that their electronic structure already approaches that of 2D-SiC. This is predicted to be flat, but some doubts have remained regarding the preference of Si for sp3 hybridization. Exploring a number of corrugated morphologies, we find completely flat 2D-SiC to have the lowest energy. We further compute its phonon dispersion, with a Raman-active transverse optical mode, and estimate the core level binding energies. Finally, we study the chemical reactivity of 2D-SiC, suggesting it is like silicene unstable against molecular absorption or interlayer linking. Nonetheless, it can form stable van der Waals-bonded bilayers with either graphene or hexagonal boron nitride, promising to further enrich the family of two-dimensional materials once bulk synthesis is achieved.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Slovak University of Technology in Bratislava, Danubia NanoTech
Journal
Scientific Reports
Volume
7
No. of pages
9
ISSN
2045-2322
Publication date
12-2017
Peer reviewed
Yes
Austrian Fields of Science 2012
103015 Condensed matter, 103018 Materials physics, 103042 Electron microscopy, 210004 Nanomaterials
ASJC Scopus subject areas
General
Portal url
https://ucris.univie.ac.at/portal/en/publications/computational-insights-and-the-observation-of-sic-nanograin-assembly-towards-2d-silicon-carbide(24e1e85f-e258-4c3a-a446-f2b789b7f4dc).html