Graphene. Coloured scanning electron micrograph (SEM) of a crumpled layer of graphene. Graphene is composed of a single layer of carbon atoms arranged in a honeycomb crystal lattice. It is both flexible and very strong. It conducts electrons faster than silicon and could one day replace silicon in applications such as nanometre (billionths of a metre) sized electronics, cheap and efficient solar panels, transparent window coatings and miniature sensing technologies. Graphene was discovered by Andre Geim in 2004.