Adsorption, clustering and reaction of hydrogen atoms on graphene

Adsorption, Clustering and Reaction of Hydrogen atoms on Graphene - Recent years have witnessed an ever growing interest in carbon-based materials. Among them, those formed by sp^2 C atoms comprise graphite, carbon nanotubes, polycyclic aromatic hydrocarbons (PAHs), and recently graphene: the one-atom thick layer of graphite. In this context, the adsorption of atoms from the gas phase on graphene can be used to tailor their electronic and magnetic properties, as already suggested for defects, with the advantage of being much easier to realize than, e.g., vacancies. We show how hydrogen atoms chemisorption induces a magnetic moment on the substrate and influences both thermodinamically and kinetically further atoms adsorptions, up to clusters formation. From the dynamical point of view many calculations have been done on the hydrogen recombination reaction on graphene and graphitic surfaces, in particular for the H2 formation via the Eley-Rideal mechanism, that involves chemisorbed species. Our study show the presence of large quantum effect in this process such as quantum reflection and product quantization signatures.