Graphene and its derivatives: switching ON and OFF.

As the thinnest material ever known in the universe, graphene has been attracting tremendous amount of attention in both materials science and condensed-matter physics since its successful isolation a few years ago. This one-atom-thick two-dimensional pseudo-infinite nano-crystal consists of sp(2)-hybridized aromatic carbon atoms covalently packed into a continuous hexagonal lattice. Graphene exhibits a range of unique properties, viz., high three-dimensional aspect ratio and large specific surface area, superior mechanical stiffness and flexibility, remarkable optical transmittance, extraordinary thermal response and excellent electronic transport properties, promising its applications in the next generation electronics. To switch graphene and its derivatives between ON and OFF states in nanoelectronic memory devices, various techniques have been developed to manipulate the carbon atomic sheets via introducing the valence-conduction bandgap and to enhance their processability. In this article, we review the utilization of electrically, thermally and chemically modified graphene and its polymer-functionalized derivatives for switching and information storage applications. The challenges posed on the development of novel graphene materials and further enhancements of the device switching performance have also been discussed.