Graphene is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice. It can be viewed as an atomic-scale chicken wire made of carbon atoms and their bonds (see image). Graphene is one of the most outstanding new materials in that it holds promises for a enormeously wide range of applications. Among others, it is a candidate material for future microelectronics, may bring fundamental new insights into quantum electrondynamics, or lead to novel composite materials (For reviews on graphene, see e.g. the publications of the manchester group at Free-standing graphene, or graphene membranes, allow unprecedented electron microscopic studies which are explored in our group. On the one hand, the graphene sheet itself is of a huge interest so that its structure, defects and edges are an obvious target for electron microscopic studies. On the other hand, graphene membranes are a highly promising support film for transmission electron microscopy: For a transmission electron microscope, there exists no perfectly transparent sample carrier (such as a glass slide in case of optical microscopy) and the strong signal of conventional support films causes many problems. Graphene, with a thickness of only one atom, constitutes the thinnest conceivable membrane. Moreover, with its regular structure its contribution to the image can be easily filtered out.


Fig. 1 Structural model of single layer graphene



Fig. 2 Atomically resolved TEM image of single layer graphene


Graphene preparation: Graphene edges, ribbons and carbon chains:

A. Chuvilin, J. Meyer, G. Algara-Siller and U. Kaiser
From graphene constrictions to single carbon chains
New J. Physics, 11, 083019 (2009)

Irradiation induced defects:

J. C. Meyer, A. Chuvilin, U. Kaiser
Electron Microscopic Studies with Graphene
Microscopy and Microanalysis, vol. 15, p. 126 (2009)