Scottish researchers have developed a process enabling production of large sheets of graphene at one hundredth the cost of existing techniques.
The method, described in the latest issue of the journal Scientific Reports, relies on a cheap type of copper, the same as used in manufacturing of lithium-ion batteries.
“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,” said Ravinder Dahiya, from the University of Glasgow, who led the research. “This more expensive form of copper often requires preparation before it can be used, adding further to the cost of the process.”
Graphene, a one-atom-thick layer of carbon atoms, was first isolated in 2004 at the University of Manchester. Since its discovery, it has been hailed for its properties such as sturdiness, light weight and electrical conductivity. It is believed that graphene will eventually revolutionise the electronics industry, enabling creation of devices with unprecedented capabilities.
However, the feasibility of graphene mass production has so far been hindering development.
The new method developed by the Glasgow team is quite similar to chemical vapour deposition, or CVD, the currently dominant method of graphene production.
The method turns gaseous reactants into a film of graphene on a special surface known as a substrate. In the case of the Glasgow-based research, this substrate was nothing else but commercially available copper foils, the exact same type as used for making negative electrodes for lithium-ion batteries. The ultra-smooth surface of the copper provided an excellent bed for the graphene to form upon.
“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,” said Dahiya.
“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 with sensation in a way that is impossible for even the most advanced prosthetics today.”
The graphene produced using the new method showed better electrical and optical properties than graphene the researchers had been able to produce earlier using the older process.