Enhanced absorption or transparency in hybrids of nanoparticles and graphene

The appealing side of nanotechnology lies in the fact that ordinary materials show surprising properties when their size is reduced to billionths of meters (nanometers). For example, we all know that silver is gray and gold is yellow, but when they are turned into nanoparticles these colors change, and the whole rainbow can be reproduced by controlling the geometrical shape and the assembly of the metals. Another famous nanotechnology example is graphene, namely what you would get if the graphite of your pencil can be spread on a sheet up to produce a layer with the thickness of one atomic layer. Scientists investigated the physical properties of these nanomaterials for several years, and many things are now well known about the optical, electronic and mechanical behaviour. However, what happens when Ag or Au nanoparticles are combined with graphene is still not well understood.