1. Graphene Sheets from worm-like graphite
Tsinghua University researchers have made high quality graphene sheets have been prepared by a facile liquid phase exfoliation of worm-like graphite (WEG). This approach combining with the advances in large scale industry manufacturing of WEG could potentially lead to the development of new and more effective graphene products.
Supplemental information is here
2. Etching of Graphene Devices with a Helium Ion Beam
We report on the etching of graphene devices with a helium ion beam, including in situ electrical measurement during lithography. The etching process can be used to nanostructure and electrically isolate different regions in a graphene device, as demonstrated by etching a channel in a suspended graphene device with etched gaps down to about 10nm. Graphene devices on SiO2 substrates etch with lower He ion doses and are found to have a residual conductivity after etching, which we attribute to contamination by hydrocarbons.
The full pdf copy of the ion beam etching of graphene.
Schematic of a graphene device. Inset: Photograph of the microscope chamber
with installed chip.