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arXiv · 0905.2114

Molecular adsorption in graphene with divacancy defects

Biplab Sanyal·Olle Eriksson·Ulf Jansson·Helena Grennberg
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Abstract

We have investigated theoretically the adsorption of molecules onto graphene with divacancy defects. Using ab-initio density functional calculations, we have found that O2, CO, N2, B2 and H2O molecules all interact strongly with a divacancy in a graphene layer. Along with a complex geometry of the molecule-graphene bonding, metallic behavior of the graphene layer in presence of CO and N2 molecules have been found with a large density of states in the vicinity of the Fermi level suggesting an increase in the conductivity. The adsorption of N2 is particularly interesting since the N atoms dissociate in the vicinity of the defects, and take the place where the missing C atoms of the divacancy used to sit. In this way, the defected graphene structure is healed geometrically, and at the same time doped with electron states.

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Biplab Sanyal, Olle Eriksson, Ulf Jansson, Helena Grennberg. 2009-05-13. Molecular adsorption in graphene with divacancy defects. https://doi.org/10.1103/physrevb.79.113409

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