Cycloaddition of metal-supported graphene interfaces: a first principles investigation
1Laboratoire de chimie UMR ENS Lyon, Lyon, France
2Current address: Laboratoire Pasteur, ENS, Paris, France
Chemistry is playing a vital role in the realization of graphene applications. The chemical formation of covalent carbon-carbon bonds involving the graphene layer potentially allows the generation of insulating and semiconducting regions, crucial for electronic devices. In particular, covalent functionalization of graphene by aromatics via Diels-Alder (DA) reactions is emerging as a facile way to achieve these goals.
The cycloaddition reactions of iron porphine with graphene epitaxed to a series of lattice-matched and lattice-mismatched metal surfaces have been investigated by using dispersion-corrected density functional theory (DFT) calculations. Our calculations evidence the non-classic cycloaddition with 3π units from graphene on specific hollow C -top C -hollow C registry areas. The feasibility of the cycloaddition depends on the nature of the metal below graphene : Ir is the most reactive metal while Re is less reactive and Cu almost inactive. 
We also propose that iron phthalocyanine reacts similarly with graphene on Ir, causing the STM disappearance of one of the four molecular lobes.  Our results provide a fertile playground to the community of chemists working on the functionalization of graphene-related substrates.
 M. Lattelais and M.-L. Bocquet, J. Chem. Phys. C, in press 2015.
 S. J. Altenburg, M. Lattelais, B. Wang, M.-L. Bocquet and R. Berndt, submitted 2015.