Enhancement of concrete properties through graphene nanotechnology is being investigate by many academic institutions. In simple terms graphene is a sheet of a single layer (monolayer) of carbon atoms, tightly bound in a hexagonal honeycomb lattice.
 

An overview of the research at the University of Exeter on the effects of graphene (Concrene Project) can be found in the June issue of CONCRETE 52/6 2018, pp61-63.