Molecular adsorption in graphene with divacancy defects

TL;DR

This study uses density functional theory to explore how various molecules interact with divacancy-defected graphene, revealing strong adsorption, potential conductivity changes, and defect healing through N2 dissociation.

Contribution

It provides a detailed theoretical analysis of molecule adsorption on defected graphene, highlighting new insights into defect healing and electronic property modifications.

Findings

Strong molecule adsorption on divacancy graphene

Metallic behavior induced by CO and N2 adsorption

N2 dissociation heals defects and dopes the graphene

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.