March 2013

Researchers from Rice University and Tsinghua University discovered (using theoretical calculations) that defects in graphene can cause it to become weak - if they occur at the grain boundaries of graphene sheets. Those grain boundaries occur because graphene grown in labs (usually using CVD) are not perfect and this creates several "islands" of graphene that merge together. The researchers say that at these points, graphene is about half as strong as perfect graphene.

The atoms on the lines that connect those islands are called grain boundaries - and the atoms at those lines usually bond in five- and seven- atom rings. These are weaker than the normal hexagon rings of graphene. The weakest points are seven-atom rings. These are found at junctions of three islands, and that's where cracks in graphene are most likely to form.

Graphene Nanochem (previously Biofutures International) successfully raised £32.5 million (almost $50 million) and acquired Malaysian specialty chemicals group Platinum Nanochem. The company now trades on the UK's AIM stock exchange (ticker GRPH) with a market value of around £155 million ($235 million).

The new company holds an existing core specialty chemicals business in Malaysia, and also holds the exclusive license to a process known as Catalyx which uses a catalyst to extract graphene from biogases (such as methane). This process can potentially mean low-cost graphene production. They are also developing graphene-enhanced lubricants for used in the extraction of shale gas.

Researchers from Harvard University developed a graphene-based electrically-tunable plasmonic mid-infrared antenna array. They say this device can be useful for multi-analyte sensors, reconfigurable meta-surfaces and optoelectronics devices.

This is the first time nanoantennas can be tuned to the mid-infrared part of the electromagnetic spectrum by simply applying a voltage. This works because a graphene sheet, placed in the nanogap of a dipole antenna, acts as an electrically tunable nano-circuit element.

Scientists from Rice University developed new ribbons made from vanadium-oxide and graphene-oxide (using a simple hydrothermal process) that make for superior Li-Ion battery cathodes. Batteries that use these new cathodes exhibit high energy and power densities. The new cathodes use materials that are relatively abundant and cheap.

The researchers found out that prototype cathodes used with halfcells can charge and discharge in 20 seconds and retain more than 90% of the capacity after more than 1,000 cycles. Those prototype cathodes were made from 84% VO2 (that hold 204 milliamp hours of energy per gram).

Researchers from Columbia University say that the electronic properties of graphene are very sensitive to the local environment. Using scanning tunneling microscopy, the researcher studied graphene films exfoliated onto cleaved mica (an ultra flat material that contains surface electric dipoles).

It turns out that graphene remains undoped immediately above the water molecules but becomes p-doped on the mica surface surrounding them. On the other hand, graphene becomes n-doped near the potassium ion regions. There are two types of n-doping in graphene: immediately above the potassium plateau there is a lot more electron doping then areas on flat regions.

Researchers from China's Zhejiang University developed a new sponge-like solid material (which they call Graphene Aerogel) made from freeze-dried carbon and graphene oxide which they say is the lightest material ever made. It's so light it can be placed on the delicate petals of a cherry blossom:

Aerogel weighs just 01.6 milligrams per cubic centimeter, just twice the density of hyrdogen.

mPhase Technologies is looking to license graphene technology, with an aim to integrate graphene into its its Smart NanoBattery Technology. The company says it is in talks with two universities who are "leaders in R&D of applications utilizing graphene".

Back in July 2012 mPhase started to collaborate with the Stevens Institute of Technology on the design and fabrication of a new battery technology that combines mPhase's Smart NanoBattery Technology with Stevens' graphene-based inkjet printing method for printing electrodes and electronic circuits.

Researchers from EPFL designed a new flash memory cell prototype that is made from graphene and Molybdenite (MoS2). They say that the new design is efficient, flexible, small and fast. The idea is that the unique electronic properties of MoS2 (it has an "ideal energy band") are combined with graphene's excellent conductivity.

The EPFL design uses field-effect geometry. A thin layer of MoS2 is in the middle layer that channels electrons. The electrodes on the top and the bottom are made from graphene.

Lockheed Martin says that they have developed a new energy-efficient graphene-based water desalination technology. Lockheed developed new graphene filters that has nanometer-sized holes in them that allow water to pass through - but not salt molecules. The energy required to "push" seawater through these filters is very low because graphene is so thin. In fact graphene is 500 times thinner than the filter available today, and this filter will require about 100 times less energy. Lockheed patented the new filtration system, and calls the new material Perforene.

Simulated nanoporous graphene filtering salt ions

Lockheed is not ready to commercialize this technology yet. They are still refining the process for making the holes in graphene, and also the production process of the graphene itself. They expect to have a prototype filter by the end of 2013. This prototype will be a drop-in replacement for current filters used in reverse osmosis (RO) plants. They hope to commercialize this technology by 2014-2015 and are looking for partners in the filter manufacturing arena.

American Graphite Technologies (AGT) and its development partner Cheap Tubes announced today that they have successfully produced graphene paper samples. Those samples are 50-150um thick and are highly conductive (about 2-3ohms resistivity across a 2" area).

Cheap Tubes is now moving to the second phase of their project, which will bring improvements to the size, conductivity and scalability of this graphene paper. They hope to achieve low cost roll-to-roll production capabilities. Cheap Tubes is also upgrading its Vermont development facility.