Graphene coatings: an efficient protection from oxidation
Author
Topsakal, M.
Şahin, H.
Çıracı, Salim
Date
2012Source Title
Physical Review B - Condensed Matter and Materials Physics
Print ISSN
2469-9950
Electronic ISSN
2469-9969
Publisher
American Physical Society
Volume
85
Issue
15
Pages
155445-7 - 155445-1
Language
English
Type
ArticleItem Usage Stats
129
views
views
114
downloads
downloads
Abstract
We demonstrate that graphene coating can provide efficient protection from oxidation by posing a high-energy barrier to the path of oxygen atom, which could have penetrated from the top of the graphene to the reactive surface underneath. A graphene bilayer, which blocks the diffusion of oxygen with a relatively higher energy barrier, provides even better protection from oxidation. While an oxygen molecule is weakly bound to a bare graphene surface and hence becomes rather inactive, it can easily dissociate into two oxygen atoms adsorbed to low-coordinated carbon atoms at the edges of a vacancy. For these oxygen atoms the oxidation barrier is reduced and hence the protection from oxidation provided by graphene coatings is weakened. Our predictions obtained from the state-of-the-art first-principles calculations of the electronic structure, phonon density of states, and reaction path will unravel how graphene can be used as a corrosion-resistant coating and guide further studies aimed at developing more efficient nanocoatings. © 2012 American Physical Society.