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arXiv · 1405.4911

Fluorine absorption on single and bilayer graphene: Role of sublattice and layer decoupling

Hernán Santos·Luc Henrard
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Abstract

The fluorination of mono- and bi-layer graphene have been studied by means of ab-initio DFT calculations. The stability of CF$_x$ systems are found to depend on both the F coverage and on the position of the F atoms regarding the C sublattices. When F atoms is chemisorbed to C atoms belonging to the same sublattice, low coverage is preferred. Otherwise, large F coverable is more stable (up to C$_4$F). The difference of charge distribution between the two carbon sublattices explains this finding that is confirmed by the analysis of the diffusion barriers. Binding energy of F on bi-layer systems is also computed slightly smaller than on monolayer and electronic decoupling is observed when only one of the layer is exposed to fluorine.

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Hernán Santos, Luc Henrard. 2014-05-19. Fluorine absorption on single and bilayer graphene: Role of sublattice and layer decoupling. https://doi.org/10.1021/jp507178f

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