The potential of graphene captured the world’s imagination when it was first isolated from graphite in 2004. The two-dimensional material, consisting of a single layer of carbon atoms in a hexagonal or “honeycomb” structure, is exceedingly strong and highly conductive. Perhaps more interestingly, it’s one million times thinner than a sheet of paper. These unique characteristics make graphene an appealing material for use in electronics, smart packaging, bioengineering, super capacitors and nanodevices to name but a few. However, while the commercial potential is substantial, until very recently, the processes used to obtain defect-free graphene yielded such minuscule amounts that development of this potential into commercial applications remained more a theoretical possibility than a reality.
Ongoing research has now established reliable methods for production of graphene in the laboratory and the next step - scaling up the process - is underway.
From the laboratory to commercial production
Silverson high shear mixers offer researchers into production of graphene a proven method to achieve scalability in graphene production. One of the successful techniques used to extract graphene from graphite is shear exfoliation in liquid. The high shear of a rotor stator mixer can exfoliate defect-free, few-layer graphene from graphite in solvent systems or certain surfactants. While working on a laboratory scale with a Silverson L5M-A, this process can be replicated fairly easily. The challenge is to duplicate the defect-free graphene production results on a large scale to enable commercialisation.
Engineered for scalability
Silverson designs, engineers and constructs its laboratory mixers to the same precision tolerances as its production units. In fact the entire Silverson range of mixers produces comparable rotor tip speeds and shear rates. Because of this, and the similarity in rotor/stator geometry all our machines produce scalable results, so replicating lab-scale results with production scale mixers is ultimately achievable.
This was demonstrated in research published in the journal Nature Materials, where a team at the Centre for Research on Adaptive Nanostructures and Nanodevices, Trinity College Dublin, Dublin, Ireland, showed scalable graphene production is possible. Silverson mixers were used in these successful graphene production trials as well as other unrelated research in the U.S. and elsewhere.
Scale-up is a core competency at Silverson that is considered in the design and manufacture of all of our mixers. And a key requirement for scaling up graphene production is consistent mixing performance. Our engineers have worked closely with both academic and industry experts on scientific research into scaling up graphene production, and as part of Silverson’s commitment to assist in developing this new technology, the company is offering the services of its fully-equipped Test Centres to allow clients to conduct trials.