Regensburg 2016 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 79: Graphene III: Electronic Properties

O 79.5: Vortrag

Donnerstag, 10. März 2016, 11:30–11:45, S053

Ultraclean Freestanding Graphene by Pt-metal catalysis — •Jean-Nicolas Longchamp, Conrad Escher, and Hans-Werner Fink — Physics Department of the University of Zurich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland

When using graphene as a substrate in electron microscopy, the presence of residues is obstructive because the latter are often of the same size as the object under study. While the growth of defect-free single-layer graphene by means of chemical vapor deposition (CVD) is nowadays a routine procedure, easily accessible and reliable techniques to transfer graphene to different substrates in a clean manner are still lacking. We have discovered a method for preparing ultraclean freestanding graphene using the catalytic properties of platinum metals. Complete catalytic removal of a sacrificial PMMA layer only requires annealing in air at a temperature between 175°C and 350°C. Here, we will describe in detail the preparation process for obtaining ultraclean freestanding graphene by Pt-metal catalysis. The presentation of low-energy electron holography and TEM investigations will demonstrate that areas of ultraclean freestanding graphene as large as 2 microns square can now routinely be prepared.