Regensburg 2016 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 61: Graphene II: Adsorption, Intercalation and Doping

O 61.8: Vortrag

Mittwoch, 9. März 2016, 16:45–17:00, S053

Molecular friction and proton dynamics in sulfuric acid intercalated graphite from ab-initio MD simulations — •Steffen Seiler and Bernd Meyer — Interdisciplinary Center for Molecular Materials and Computer-Chemistry-Center, FAU Erlangen-Nürnberg

Wet-chemical exfoliation of graphite via Hummers’ method [1,2] is a promising route for large-scale graphene production. In this solution-based process first graphite is intercalated by concentrated sulfuric acid, then the graphite intercalation compound (GIC) is oxidized, graphene oxide (GO) layers are separated in solution by hydrolysis reactions, and finally the GO layers are reduced to graphene [3].
We performed Car-Parrinello molecular dynamics (CP-MD) simulations to study the dynamic properties of the liquid sulfuric acid within the confined space between the graphene layers. The friction coefficient, proton-transfer barriers and electron distributions have been analyzed, and we will show how these properties are affected by the oxidation and the stacking sequence of the graphene sheets. Finally, consequences for the mechanism of GIC formation and oxidation will be discussed.

[1] W. S. Hummers, J. Am. Chem. Soc. 80, 1339 (1958).
[2] D. C. Marcano et al., ACS Nano 4, 4806 (2010).
[3] A. M. Dimiev and J. M. Tour, ACS Nano 8, 3060 (2014).