It is one atom thick and touted to be stronger than steel. Graphene has captured the scientific and public imagination as the wonder material of the 21st century. Now, researchers at Trinity College Dublin have found a way to extract the substance from graphite – using a kitchen blender and some liquid soap.
Since Konstantin Novoselov and Andre Geim of Manchester University managed to extract graphene (which is a two-dimensional slice of graphite) using a piece of transparent tape, the buzz around this super-strong, super-conductive material has tended toward the superlative. Novoselov and Geim received the Nobel Prize for their discoveries in 2010, but still the quest continues for a method of scaling up graphene extraction to an industrial, or even a vaguely practical level.
Now, researchers at Trinity College Dublin have found a new and relatively quick way to obtain graphene from a sample of graphite, and their revolutionary equipment consists of a modest kitchen blender and liquid detergent. According to Dr. Keith Paton, who worked on the project, this was a "sighting" experiment, which was carried out "to test the feasibility of using shear mixing to exfoliate graphene."
The researchers realized they needed a surfactant to keep the flakes separated and dispersed in the liquid. Again, they decided to begin with the most available source, regular liquid dish-washing detergent, and they found that this worked nearly as well as an industrial product.
Dr. Paton likens the process to "sliding your hands across a deck of cards," causing them to spread and separate. After being exfoliated in flakes, the graphene can be recovered in a number of ways, including using filtering processes or by allowing the liquid to evaporate. The experiment with the rotor-stator proved that the blender method could be scaled up to an industrial level of production, and this is what is getting people excited.
Graphene could also be used for very thin, flexible, perhaps more efficient and transparent solar cells. And there is significant potential in strengthening plastics. Since a very minute amount of graphene can improve the strength of PET (plastic used widely in drink bottles) by around 40 percent, this could result in a huge reduction in the amount of plastic required.
All that having been said, two separate studies have recently raised concerns about the dangers that graphene could pose both to ourselves, and to the environment.
While it may seem to have burst onto the scene, experiments with graphene go back at least to 2004, when Novoselov and Geim conducted their tape experiment. This latest discovery was the outcome of a collaborative project between Thomas Swan (manufacturer of specialty chemicals) and CRANN (the Centre for Research on Adaptive Nanostructures and Nanodevices) at Trinity College Dublin. The work was carried out at CRANN where the team was led by Professor Jonathan Coleman.
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