Researchers have examined several materials to be used as substrates for Graphene, trying to find a material that will preserve Graphene's properties. One such materials is Haxagonal Boron Nitride. It's just 1.7% larger than graphene and exhibits dramatically better electron mobility than graphene mounted on silicon dioxide, SiO2, which is the most commonly used material.
Researchers from Texas State University developed a new method for creating single-crystal arrays of graphene. This is seen as an advance towards manufacturing large quantities of single crystals of Graphene - similar to Silicon wafer production.
The idea is to initiate graphite 'seeds' - hexagonal single crystals, and then grow them on top of a copper foil inside a chamber containing methane gas using a process called chemical vapor deposition. This method can be used to grow an ordered array of thousands or millions of single crystals of graphene.
NIST researchers say that defects in Graphene may appear due to the movement of the carbon atoms at high temperatures when producing graphene by heating silicon carbide under ultrahigh vacuum. Graphene tend to rearrange from six-sided rings to five or seven atoms. Stringing five and seven member rings together in closed loops creates a new type of defect or grain boundary loop in the honeycomb lattice. These defects might allow it a little flexibility, making Graphene even more resilient to tearing or fracturing.
The researchers say that we should be able to either avoid defects entirely or produce them at will by variations in growth conditions.
Researchers from Asia demonstrated that graphene provides a promising biocompatible scaffold that does not hamper the proliferation of human mesenchymal stem cells (hMSCs) and accelerates their specific differentiation into bone cells. The differentiation rate is comparable to the one achieved with common growth factors, demonstrating graphene's potential for stem cell research.
Researchers from Turkey's Bilkent University discovered that graphene oxide can be reversibly reduced and oxidized using electrical stimulus. They say that graphene's band structure can be electrochemically tuned in ambient air in a two terminal planar device (due to humidity in the air). The researchers claim that if this effect can be better controlled, you could use this to create E Ink like e-paper that will be ultrafast. This could also have applications in information processing.
Here's a video showing controlled reduction and oxidation in two-terminal devices (containing multilayer graphene oxide films):
Researchers from the University of California, Berkeley built an optical modulator (switches light on and off) using Graphene. This is the basis of network modulators (which use light to transmit data). The graphene based modulator is the world's smallest and fastest - which could help create faster communication devices. In fact Graphene can be used to create modulators that are up to ten times faster than any current technology based modulators.
The researchers found out that tuning graphene electrically (applying voltage) causes it to absorb light in wavelength that are used for data communications (it alters the Graphene's Fermi level). At certain voltages Graphene becomes transparent, and lets light through. If you change the voltage around that level you can change whether the material is transparent or not - and basically it becomes a light switch.
Dr. Atul Tiwari, an associate researcher at University of Hawaii (UH M?noa) developed a synthetic procedure to create a graphene sheet - that does not require a binder. The new method can be used to manufacture super long graphene films, and the procedure can be adopted to manufacture this sheet continuously as roll-to-roll.
The film can also be dissolved completely in a solvent by adopting an ultra-sonication technique or be rolled between the two sheets of paper and thus can be transported without the need of special shipping and packaging.
The European Commission suggests a 10-year large-scale €1 billion research initiative (coordination action) on Graphene called GRAPHENE-CA. The EU wants to secure a major role in the upcoming Graphene 'revolution'.
The GRAPHENE-CA already includes over 130 research groups, representing 80 academic and industrial partners in 21 European countries. A pilot phase began on May 1st and in 2012 the GRAPHENE-CA will be submitted to the commission. In 2013, they will choose two flagship projects, one of these will hopefully be GRAPHENE-CA.