Abstract:In order to progress from the lab to commercial applications it will be necessary to develop industrially scalable methods to produce large quantities of defect-free graphene.Here we show that high-shear mixing of graphite in suitable, stabilizing liquids results in large-scale exfoliation to give dispersions of graphene nanosheets. XPS and Raman spectroscopy show the exfoliated flakes to be unoxidised and free of basal plane defects. We have developed a simple model which shows exfoliation to occur once the local shear rate exceeds 10 4 s -1 . By fully characterizing the scaling behaviour of the graphene production rate, we show that exfoliation can be achieved in liquid volumes from 100s of ml up to 100s of litres and beyond. The graphene produced by this method performs well in applications from composites to conductive coatings. This method can be applied to exfoliate BN, MoS2 and a range of other layered crystals. Main Text:Due to its ultra-thin, 2-dimensional nature and its unprecedented combination of physical properties, graphene has become the most studied of all nano-materials. In the next decade graphene is likely to find commercial applications in many areas from high-frequency electronics to smart coatings.

We report here on the synthesis and characterization of silicon oxycarbide (SiOC) in view of its application as a potential anode material for Li-ion batteries.

Graphene tunnel junctions are a promising experimental platform for single molecule electronics and biosensing. Ultimately their noise properties will play a critical role in developing these applications. Here we report a study of electrical noise in graphene tunnel junctions fabricated through feedback-controlled electroburning. We observe random telegraph signals characterized by a Lorentzian noise spectrum at cryogenic temperatures (77 K) and a 1/ f noise spectrum at room temperature. To gain insight into the origin of these noise features, we introduce a theoretical model that couples a quantum mechanical tunnel barrier to one or more classical fluctuators. The fluctuators are identified as charge traps in the underlying dielectric, which through random fluctuations in their occupation introduce time-dependent modulations in the electrostatic environment that shift the potential barrier of the junction. Analysis of the experimental results and the tight-binding model indicate that the random trap occupation is governed by Poisson statistics. In the 35 devices measured at room temperature, we observe a 20-60% time-dependent variance of the current, which can be attributed to a relative potential barrier shift of between 6% and 10%. In 10 devices measured at 77 K, we observe a 10% time-dependent variance of the current, which can be attributed to a relative potential barrier shift of between 3% and 4%. Our measurements reveal a high sensitivity of the graphene tunnel junctions to their local electrostatic environment, with observable features of intertrap Coulomb interactions in the distribution of current switching amplitudes.

We report room-temperature Coulomb blockade in a single layer graphene three-terminal singleelectron transistor (SET) fabricated using feedback-controlled electroburning. The small separation between the side gate electrode and the graphene quantum dot results in a gate coupling up to 3 times larger compared to the value found for the back gate electrode. This allows for an effective tuning between the conductive and Coulomb blocked state using a small side gate voltage of about 1V. The technique can potentially be used in the future to fabricate all-graphene based room temperature singleelectron transistors or three terminal single molecule transistors with enhanced gate coupling.Due to its 2D character and high charge carrier mobility graphene is one of the most promising materials for future electronics. 1 Progress in chemical vapour deposition growth allows for the fabrication of graphene foils with sizes up to 750 mm or more. 2 Graphene can be patterned with dimensions down to a few nanometres using standard lithography techniques, 3,4 which opens up the possibility of scalable fabrication of graphene based nanoelectronics. 5 Graphene quantum dots have been successfully fabricated by means of lithography 3 and electroburning techniques 6,7 . The latter allows the formation of single electron transistors (SETs) with addition energies up to 1.6 eV, enabling room temperature

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