Oxford University designs a technique for commercial-scale production of high-quality graphene sheets

Oxford University researchers have developed a method for producing graphene in large high-quality sheets. The university's technology commercialization branch, Isis Innovation, states that the researchers had solved a major barrier to the development of the material, making commercial-scale sheets of repeatable and uniform quality graphene ready for production.

The technique, currently in the process of patent application, enables the manufacture of commercial scale graphene sheets using a transition metal substrate combined with an intermediate silicon containing liquid film. The graphene sheets are made using CVD and large, high-quality graphene flakes are produced. Synthesis times are reduced by 50 times, according to Isis, adding that it was looking for commercial partners. 

Read the full story Posted: Jun 18,2015

Grinding nanotubes yields graphene nanoribbons

Researchers at Rice University, the Indian Institute of Technology and the Lebanese American University discovered that grinding carbon nanotubes might be a simple way of forming graphene nanoribbons. The research indicates that a simple process like grinding could deliver strong chemical coupling between solid nanostructures and produce novel forms of products with specific properties.

The scientists mixed two types of chemically modified nanotubes (one with carboxyl groups and the other with hydroxyl groups attached) and ground them together for about 20 minutes using a mortar and pestle. They noticed that when the two types of nanotubes come into contact during grinding, they react and unzip, a process that until now has depended largely on reactions in specific chemical solutions.

Read the full story Posted: Jun 17,2015

Graphene as a substrate for assembling small organic molecules and heterostructures

Researchers at the University of Stanford in the US, the Ulsan National Institute of Science and Technology (UNIST) in South Korea and Queen’s University in the UK showed that graphene is an excellent substrate for assembling small organic molecules and that such heterostructures might be used in applications like high-performance detectors, solar cells and flexible transistors.

The researchers began by preparing suspended graphene films. They then evaporated C60 molecules onto the films to form thin-film crystals.They then made the resulting structures up into vertical transistors doped with n-type semiconducting materials and found that these devices have current on/off ratios of more than 3 x 103. Various transmission electron microscopy techniques, including selective area electron diffraction, atomic resolution TEM imaging, and van der Waals-based first principles computational methods allowed the researchers to study the structure and grain size of the crystals in detail and carefully look at the graphene-C60 interface in particular. They also noticed that the C60 films lay uniformly on the graphene substrate and that the individual molecules can assume several different molecular orientations.

Read the full story Posted: Jun 17,2015

Porous graphene envelope improves performance of platinum catalysts and may improve fuel cells

Researchers at the Korean Institute of Energy Research (KIER) and the University of Oxford in the UK showed that encapsulating platinum nanoparticles with nitrogen-doped graphene layers improves the catalytic activity of the particles, while making them more resistant to degradation. This could lead to better proton exchange membrane fuel cells (PEMFCs) in the future.

The scientists state that without the nitrogen treatment, the Ptgraphene nanoparticle is very resilient to degradation, but it also becomes a rather ineffective catalyst. The nitrogen treatment appears to 'puncture' the graphene shell, allowing the Pt underneath to catalyze reactions while being protected from the acidic electrolyte in a fuel cell. The researchers found that the porous graphene encapsulated Pt nanoparticles were almost as good as bare Pt nanoparticles in terms of catalytic performance (with a peak efficiency of 87% compared to bare Pt) but that they did not degrade compared to the bare particles.

Read the full story Posted: Jun 17,2015

2-DTech achieves major advance in graphene production

Versarien, the advanced engineering materials group, recently announced that its graphene development subsidiary, 2-DTech, has achieved a major breakthrough in graphene production. The 2-DTech production process provides significant amounts of single layer graphene on an industrial scale.

The company believes that this significant advance will accelerate potential commercial applications for graphene and graphene products. As a result of 2-DTech's investment program, it has developed its own proprietary graphene production technique founded upon a licensed process from University of Ulster.

Read the full story Posted: Jun 17,2015

Scientists explore the effects of grain boundaries on graphene's heat conduction

Researchers at the University of Illinois at Chicago, the University of Massachusetts-Amherst and Boise State University explored the effects of boundaries between grains of graphene on its heat conductivity by developing a technique to measure heat transfer across a single grain boundary. 

The surprising results revealed an order of magnitude (about 10 times) lower than the theoretically predicted value. The scientists then devised computer models that can explain the surprising observations from the atomic level to the device level. The team developed an experimental system that lays down a graphene film onto a silicon-nitrate membrane around four-millionths of an inch thick and can measure the transfer of heat from one single graphene crystal to another. The system is sensitive to even the tiniest changes, like nano-scale grain boundary. When two crystals are neatly lined up, heat transfer occurs as predicted by theory. When two crystals have mis-aligned edges, though, the heat transfer that occurs is 10 times less. 

Read the full story Posted: Jun 17,2015

New article: introduction to graphene paints

One exciting application of graphene is in the paints industry. Graphene's high resistivity can make for durable coatings that do not crack and are resistant to water and oil, its excellent electrical and thermal conductivity can be used to make various conductive paints, and a strong barrier effect can contribute to extraordinary anti-oxidant, scratch-resistant and anti-UVA paints. Don't miss our new article that introduces Graphene Paints.

Paint sample photo

Read the full story Posted: Jun 16,2015

KAIST scientists create novel graphene QD LEDs

Researchers from Korea Advanced Institute of Science and Technology (KAIST) have fabricated light-emitting diodes (LEDs) based on graphene quantum dots (GQDs). The researchers made pure GQDs using a cost-effective, scalable and environmentally friendly method that allows direct fabrication of GQDs using water, without surfactants or chemical solvents.

Those GQDs were then used as emitter material to create an OLED device.The scientists constructed GQD LEDs exhibiting luminance of 1000 cd/m2, which is well over the typical brightness levels of the portable displays used in smartphones.

Read the full story Posted: Jun 16,2015

Graphene enables tiny bulb on a chip

A team of scientists from Columbia, Seoul National University (SNU), and Korea Research Institute of Standards and Science (KRISS) reported the creation of an on-chip visible light source using graphene as a filament. Creating light in small structures on the surface of a chip is crucial for developing fully integrated 'photonic' circuits that do with light what is now done with electric currents in semiconductor integrated circuits.

The scientists attached small strips of graphene to metal electrodes, suspended the strips above the substrate, and passed a current through the filaments to cause them to heat up. The team refers to this design as 'the world's thinnest light bulb', a type of 'broadband' light emitter that can be integrated into chips and may pave the way towards the realization of atomically thin, flexible, and transparent displays, and graphene-based on-chip optical communications.

Read the full story Posted: Jun 16,2015

Carbon Sciences to develop graphene-based devices for cloud computing

Carbon Sciences announced its plans to develop graphene-based devices for cloud computing. Graphene-based fiber optics components, such as photodetectors, fiber lasers and optical switches, are expected to unclog the existing bottlenecks and enable ultrafast communication in data centers for Cloud computing.

The company states that it is shifting its focus to high value, large market opportunities to apply the knowledge gained from years of exploring methods to produce low cost graphene. Carbon Sciences estimates that contrary to many other applications that are years away from finding commercial success, cloud computing can soon create one of the most significant market opportunities in the world. By exploiting the excellent optical and electrical properties of graphene, the company plans to develop next generation fiber optics components that are ultrafast, low power and low cost.

Read the full story Posted: Jun 16,2015