
Researchers cut cost of graphene production
Graphene has been hailed as a ‘wonder material’ since it was first isolated from graphite in 2004. Graphene is just a single atom thick but it is flexible, stronger than steel, and capable of efficiently conducting heat and electricity.
However, widespread industrial adoption of graphene has so far been limited by the expense of producing it. Affordable graphene production could lead to a wide range of new technologies reaching the market, including synthetic skin capable of providing sensory feedback to people with limb prostheses.
In a new paper published in the journal Scientific Reports, the researchers outline their process. Graphene is often produced by chemical vapour deposition, CVD, (a process familiar in semiconductor manufacturing) in which gaseous reactants deposit into a film of the desired product on a substrate.
Prior work has used copper that, at a microscopic scale, has surface scratches and defects caused by the rolling process that produces it. The research team instead turned to a copper foil – commercially available ultra-smooth Cu foil by Mitsui Mining and Smelting – that is volume-manufactured for use as the negative electrodes in lithium-ion batteries. The ultra-smooth surface of the copper provided an excellent bed for the graphene to form upon.
They found that the graphene they produced offered a marked improvement in the electrical and optical performance of transistors which they made compared to similar materials produced from the older process; among other improvements, the graphene covered the substrate more completely, and was better-structured with fewer defects in the film.
Dr Dahiya, of the University of Glasgow’s School of Engineering, said: ““The commercially-available copper we used in our process retails for around one dollar per square metre, compared to around $115 for a similar amount of the copper currently used in graphene production. This more expensive form of copper often required preparation before it can be used, adding further to the cost of the process.
“Our process produces high-quality graphene at low cost, taking us one step closer to creating affordable new electronic devices with a wide range of applications, from the smart cities of the future to mobile healthcare.
“Much of my own research is in the field of synthetic skin. Graphene could help provide an ultraflexible, conductive surface which could provide people with prosthetics capable of providing sensation in a way that is impossible for even the most advanced prosthetics today.
The research was conducted by the University of Glasgow in partnership with colleagues at Bilkent University in Turkey.
The team’s paper, titled ‘Synthesis of Large Area Graphene for High Performance in Flexible Optoelectronic Devices’, is published in Scientific Reports and is available at www.nature.com/articles/srep16744. The research was funded by the European Commission and the Engineering and Physical Sciences Council (EPSRC).
University of Glasgow; www.glasgow.ac.uk
