Sep 9, 2013
Graphene production goes green
Graphene has attracted much attention both in academia and industry thanks to its outstanding physical, chemical and mechanical properties. Several methods to scalably synthesize graphene already exist but most of these techniques are either too expensive or environmentally unfriendly since they rely on the use of toxic chemicals. The search to find a facile, cost-effective and eco-friendly method for mass producing functionalized graphene is thus still on. In our new paper, we describe the "green" synthesis of monolayer-functionalized graphene by a one-step electrochemical exfoliation of graphite under a constant electrical potential.
We used a low molecular weight organic molecule, 6-amino-4-hydroxy-2-naphthalenesulphonic acid (ANS), as the electrolyte for exfoliating graphite and simultaneously modified the surface of the produced graphene sheets through π-π interactions. We confirmed the formation of functionalized graphene by X-ray diffraction, Fourier transform infrared, Raman and X-ray photoelectron spectroscopy. Transmission electron microscopy and atomic force microscopy also confirmed the formation of few-layer graphene.
These electrochemically-synthesized materials could be very useful for energy storage application as suggested by our cyclic voltammetry, charge-discharge and electrochemical impedance spectroscopy data analysis. Charge-discharge experiments have also shown that the specific capacitance of ANS functionalized graphene is 115 F g–1 at a current density of 4 A g–1.
More information can be found in the journal Nanotechnology24 365706.
Laser beam exfoliates graphite to form chemically tunable platform (Jan 2013)
New approach to scalable nano-patterning of graphene (Nov 2011)
Scaling up graphene nanoribbons – a bioinspired solution (Sep 2009)
About the author
This study was conducted by Prof. Joong Hee Lee’s research team at Chonbuk National University, South Korea. Lee’s group is actively involved in the synthesis of monolayer graphene by chemical, electrochemical and chemical vapour deposition techniques. The team is also working on graphene-based energy storage supercapacitor devices and some members of the team are also looking into the development of cost effective, highly sensitive and selective bio-sensing electrode materials for the detection of biomolecules in physiological solution. At present there are five postdoctoral research associates, eight PhD students, 15 Masters and three Bachelor students working on graphene-based materials for the development of next-generation energy storage, optoelectronic and biomedical devices.