Direct imaging of lattice atoms and topological defects in graphene membranes.
We present a transmission electron microscopy investigation of graphene membranes, crystalline foils with a thickness of only 1 atom. By using aberration-correction in combination with a monochromator, 1-A resolution is achieved at an acceleration voltage of only 80 kV. The low voltage is crucial for the stability of these membranes. As a result, every individual carbon atom in the field of view is detected and resolved. We observe a highly crystalline lattice along with occasional point defects. The formation and annealing of Stone-Wales defects is observed in situ. Multiple five- and seven-membered rings appear exclusively in combinations that avoid dislocations and disclinations, in contrast to previous observations on highly curved (tube- or fullerene-like) graphene surfaces.
Materials Sciences Division, Lawrence Berkeley National Laboratory and Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
Jannik C
JC
Meyer
C
C
Kisielowski
R
R
Erni
Marta D
MD
Rossell
M F
MF
Crommie
A
A
Zettl