2D materials beyond graphene: the case of silicene

The fascinating electronic properties of free-standing graphene has led to the exploration of alternative single-element two-dimensional (2D) materials, such as silicene, germanene, stanene, etc. which display significant analogies to graphene (Dirac cones). The synthesis of these systems on solid surfaces, however, poses questions on the preservation of their 2D character. In this talk I will present the case of silicene on Ag(111) and show how symmetry-selective hybridization destroys the ?-derived Dirac cone features near the Fermi level, while ?-derived bands at deeper energies are negligibly affected by the substrate. In perspective, I will discuss the possibility of synthesizing 2D silicon (and other materials) in suspended graphene bi-layers.