TEM images of a MgO crystal coated in graphene layers. Graphene layers are highlighted in image B. (i) Graphene layer roots on the MgO crystal. (ii) Wrinkle formation due to growth process.

Example of an etch track in graphite (a) with 45° degree angles; (b) visualization of the 45° angle in graphite.

Direct determination of etch direction from HRTEM: (a) HRTEM micrograph of Co particle at the track front; (b) Fourier enhanced TEM micrograph of the marked area in (a); (c) reconstructed image of the marked area in (b) produced by using a mask applied to the 2-D fast Fourier transform of the image; (d) Schematic view of the graphite lattice defi ning the graphite unit cell (yellow), the crystallographic directions and the zigzag and armchair edges. (Details of the carbon hydrogenation process: 775 °C, 5 min in 60 mbar H2, plus 5 min in vacuum).

(a) HRTEM image of the Moire pattern produced in a bilayer structure. (b) Structural representation of two graphene layers with 30° rotation. (c) Overlay of the structural representation in panel b with the HRTEM image in panel a, showing excellent agreement with the areas of contrast. (d) Schematic diagram illustrating two graphene layers with 30° rotation added together to produce a superstructure. (e) HRTEM image of the superstructure illustrated in panel d. (f) HRTEM image simulation of the superstructure illustrated in panel d and imaged in panel e showing excellent agreement.

(in collaboration with University of Oxford)

M.H. Ruemmeli, C.G. Rocha, F. Ortmann, I. Ibrahim, H. Sevincli, F. Boerrnert, J. Kunstmann, A. Bachmatiuk, M. Poetschke, M. Shiraishi, M. Meyyappan, B. Buechner, S. Roche, G. Cuniberti, Graphene: Piecing it together, Advanced Materials 23 (2011), S. 4471-4490 URL

F. Schaeffel, M. Wilson, A. Bachmatiuk, M.H. Ruemmeli, U. Queitsch, B. Rellinghaus, G.A.D. Briggs, J.W. Warner
Atomic resolution imaging of the edges of catalytically etched suspended few-layer graphene, ACS nano 5 (2011) Nr. 3, S. 1975-1983 URL

A. Scott, A. Dianat, A. Boerrnert, A. Bachmatiuk, S. Zhang, J.H. Warner, E. Borowiak-Palen, M. Knupfer, B. Buechner, G. Cuniberti, M.H. Ruemmeli
The catalytic potential of high-k dielectrics for graphene formation, Applied Physics Letters 98 (2011) Nr. 7, S. 73110/1-3

J.H. Warner, M.H. Ruemmeli, A. Bachmatiuk, B. Buechner
Examining the stability of folded graphene edges against electron beam induced sputtering with atomic resolution, Nanotechnology 21 (2010) Nr. 32, S. 325702/1-6 URL

M.H. Ruemmeli, A. Bachmatiuk, A. Scott, F. Boerrnert, J.H. Warner, V. Hoffman, J.-H. Lin, G. Cuniberti, B. Buechner
Direct low-temperature nanographene CVD synthesis over a dielectric insulator, ACS Nano 4 (2010) Nr. 7, S. 4206-42 URL

J.H. Warner, M.H. Ruemmeli, L. Ge, T. Gemming, B. Montanari, N.M. Harrison, B. Buechner, G.A.D. Briggs
Structural transformations in graphene studied with high spatial and temporal resolution, Nature Nanotechnology 4 (2009) Nr. 8, S. 500-504

J.H. Warner, M.H. Ruemmeli, T. Gemming, B. Buechner, G.A.D. Briggs
Direct imaging of rotational stacking faults in few layer graphene, Nano Letters 9 (2009) Nr. 1, S. 102-106 URL

F. Schaeffel, J.H. Warner, A. Bachmatiuk, B. Rellinghaus, B. Buechner, L. Schultz, M.H. Ruemmeli
Shedding light on the crystallographic etching of multi-layer graphene at the atomic scale, Nano Research 2 (2009), S. 695-705 URL

M.H. Ruemmeli, C. Kramberger, A. Grueneis, A. Ayala, T. Gemming, B. Buechner, T. Pichler
On the graphitization nature of oxides for the formation of carbon nanostructures, Chemistry of Materials 19 (2007) Nr. 17, S. 4105-4107 URL




Prof. Dr. Mark H. Rümmeli

Postal address:
IFW Dresden e. V.
PF 270116
01171 Dresden

Visitor address:
IFW Dresden e. V.
Helmholtzstraße 20
01069 Dresden

+49 (0)351 4659-510

+49 (0)351 4659-313