Perspective: The dawning of the age of graphene.

Graphene is a single sheet of carbon atoms that constitutes the basic building block of macroscopic graphite crystals. Held together by a backbone of overlapping sp(2) hybrids, graphene's 2p orbitals form π state bands that delocalize over an entire 2-dimensional macroscopic carbon sheet leading to a number of unusual characteristics that include large electrical and thermal conductivities. Recent discoveries have provided simple methods (e.g., mechanical cleavage of graphite) for preparing laboratory scale samples that can be used to investigate the fundamental physical and chemical characteristics of graphene. In addition, a number of techniques have emerged that show promise for producing large-scale samples with the ultimate goal of developing devices that take advantage of graphene's unusual properties. As large samples become available, the possibility grows for applications of this material in solar cell technology (as flexible, transparent electrodes), in composite material development, and in electronic devices.