Direct Imaging of a Two-Dimensional Silica Glass on Graphene

Author(s)
Pinshane Y. Huang, Simon Kurasch, Anchal Srivastava, Viera Skakalova, Jani Kotakoski, A. Krasheninnikov, Robert Hovden, Qingyun Mao, Jannik C. Meyer, Jürgen H. Smet, David A. Müller, Ute Kaiser
Abstract

Large-area graphene substrates provide a promising lab bench for synthesizing, manipulating, and characterizing low-dimensional materials, opening the door to high-resolution analyses of novel structures, such as two-dimensional (2D) glasses, that cannot be exfoliated and may not occur naturally. Here, we report the accidental discovery of a 2D silica glass supported on graphene. The 2D nature of this material enables the first atomic resolution transmission electron microscopy of a glass, producing images that strikingly resemble Zachariasen's original 1932 cartoon models of 2D continuous random network glasses. Atomic-resolution electron spectroscopy identifies the glass as SiO2 formed from a bilayer of (SiO4)(2-) tetrahedra and without detectable covalent bonding to the graphene. From these images, we directly obtain ring statistics and pair distribution functions that span short-, medium-, and long-range order. Ab initio calculations indicate that van der Waals interactions with graphene energetically stabilizes the 2D structure with respect to bulk SiO2. These results demonstrate a new class of 2D glasses that can be applied in layered graphene devices and studied at the atomic scale.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Cornell University, Universität Ulm, Max-Planck-Institut für Festkörperforschung, University of Helsinki
Journal
Nano Letters: a journal dedicated to nanoscience and nanotechnology
Volume
12
Pages
1081-1086
No. of pages
6
ISSN
1530-6984
DOI
https://doi.org/10.1021/nl204423x
Publication date
2012
Peer reviewed
Yes
Austrian Fields of Science 2012
210006 Nanotechnology
Portal url
https://ucrisportal.univie.ac.at/en/publications/direct-imaging-of-a-twodimensional-silica-glass-on-graphene(fc3df551-724b-44b9-9df5-6d89c1dc1492).html