The UK is undoubtedly a pioneer in graphene research, but Louise Smyth assesses whether it could also lead the way in the commercialisation of this new wonder material
For something that’s not even visible to the naked eye, graphene is causing a hell of a lot of excitement among scientists and design engineers. When you consider its much-heralded properties (200 times stronger than steel, the world’s most conductive material, one million times thinner than a human hair), the appeal for designers is clear. The tricky part, however, is how we can exploit these properties in real-world applications – in other words, how to take graphene out of the science lab and into industry.
One man well placed to address this issue is James Baker, business director for graphene at the University of Manchester (the self-described ‘home of graphene’ due to it being isolated there in 2004). Baker is overseeing the completion of the National Graphene Institute at the university, a £61million facility for graphene research that’s due to come online in early 2015. His background in industry (working for the likes of BA Systems) will stand him in good stead as he tries to take graphene to the next level. “My role focuses on finding the industrial partners that will work alongside the academics and researchers to take graphene from science and into application,” he explains.
He’s not short on those researchers either, with 200 of them at Manchester alone, working in physics, chemistry, materials science and biomedical applications for the ‘wonder material’. Neither is he lacking in potential uses for it. “Due to its qualities (for instance it is strong, flexible, transparent and more conductive than copper) we’re hearing about its use in applications ranging from electronics to structures through to membranes and coatings – there’s not an application you can think of where graphene might not have an effect.”
But as Baker observes, there are two main hurdles to be addressed before this vast potential can be realised. “The challenges today are ‘how do you produce the graphene in the purity (or the specification, if you like) that’s needed for these applications?’ And ‘how do you make sure those great properties are retained when you mix the graphene with something else?’”
Baker reveals that the National Institute will be setting out to answer these questions in various ways while also attempting to address the whole issue of ‘quality standards’. He details: “One thing the Institute is hoping to do is to try to put some framework around quality certification – i.e. ‘this is a form of graphene and here are the critical qualities you need to retain if you’re going to use it in this particular application’. It would be very difficult to commercialise any product if, every time you bought some raw material, it had a different form, property or specification.” He adds: “My background is in aerospace, where you must have that aspect tied down before you can consider putting it into a flying application. If the properties varied by more than a small natural amount you’d have to qualify/certify for every material you want to fly – which would cost a fortune.”
Yet in the consumer sector there are already companies selling graphene-based products without any form of standardisation being in place. Baker cites a well known tennis racquet firm that is currently offering a ‘graphene’ tennis racquet. He says: “It’s 99.9% graphite. But on the positive side, it does have a small amount of graphene and that does appear to have transformed or altered the properties of the structure – in that it’s more lightweight.”
Other consumer applications will be among the first commercial examples of graphene-based products, with mobile phone screen covers coming first. Baker also says: “And if you can get the phone itself flexible, you could have bent screens, curved screens or you could even have a phone that you could fold in half if the rest of the components were also bendable.”
Away from the consumer sector Baker sees lots of interest in getting graphene into various energy-related applications – such as supercapacitors and batteries. He comments: “The area that really gets me excited is that you could have structures that have battery or capacitor properties – you could store energy in an aircraft wing, for example. That would give you more endurance, so UAVs could stay in the air for longer, for instance. That’s a huge area, though there’s interest across the spectrum; from the battery in your iPad or phone to aerospace/automotive and broader energy applications.”
Baker adds: “The area I haven’t touched on yet is around membranes and barriers. Again there’s a huge interest and the university is leading the research around desalination. The ultimate theory is the graphene drinking straw: you put it into water and only pure water would come through. Questions being asked here include ‘can we add a filter to an existing plant or process?’ If you take a cup of seawater, put a little bit of pressure on it through a graphene filter, then potentially you could get drinking water through the other side.”
As well as the technical challenges addressed above, Baker also explains how there’s one more element standing in the way of concepts such as the graphene drinking straw, and that’s politics. “It’s a transformational technology and for traditional players who have always done things in certain ways – e.g. have always worked in steel or aluminium, when a new material comes along that completely changes the way you design things, that can be a big barrier to entry.
“There are two views at the moment; there are people who see graphene as a big opportunity and people who see it as a huge threat. By working closely with partners from industry, we’re trying to bridge that ‘valley of death’ and increase the probability of success.”
Another organisation working with that aim in mind is the Graphene Special Interest Group (SIG), part of the UK’s Knowledge Transfer Network (KTN). Head of the Graphene SIG, Nabil Zahlan, explains that, “the Graphene SIG was established to be a focus point for the large UK-based community of individuals and organisations working to commercialise graphene.”
Zahlan echoes Baker’s thoughts on how graphene has been associated with many applications based on its theoretical characteristics. He says: “Many of the functionalities have been demonstrated in the lab but few have appeared in commercial applications.” Due to interest in so many areas, Zahlan feels that “it is difficult to predict which applications will come next”. But he believes, “those that utilise the platelet format of graphene have an advantage of material availability.”
Zahlan thinks that what happens next in the story of graphene is “in the hands of application developers.” However, he does acknowledge the difficulty in encouraging commercial organisations to start this type of development work now. “The main hurdle is the absence of evidence or conviction that graphene will deliver the promised functional advantage within actual applications at a competitive cost. It is likely that a number of the indicated applications could work, but the question of how the use of graphene will compare with incumbent and alternative technologies remains untested. To move closer to commercialisation, application developers need to address this question by considering and testing graphene within the application. This will allow the application developer to consider all aspects of the use of graphene, including its functional performance, its incorporation into the application and the cost of use; the advantage over alternatives must be demonstrated.”
R&D in Surrey
Looking into these kind of issues for some highly specific applications is Professor Ravi Silva and his team at the Advanced Technology Institute of the University of Surrey, which is due to open a Graphene Research Centre shortly. He states: “We are interested in building on our existing long experience in the development of carbon nanomaterials by integrating graphene into smart coatings technology solutions, and in particular, in microelectronics applications.
“The carbon nanomaterial family, which includes graphene, can enhance properties of common materials - such as steel or plastics - by improving corrosion resistance, reducing gas permeation or allowing for active opto-electronic coatings. Of course, the greatest attention is to the extraordinary electronic properties that could augment a number of current application areas, which we will focus on together with our Microwave Electronics centre.”
Silva reveals that the university is strengthening links with a number of large multinationals that are backing the Graphene Research Centre, to apply graphene and related material in coatings. He adds: “We are also involved in national (EPSRC, DSTL) and European projects examining the properties of graphene and related materials, as well as their applications. Our aim is to produce graphene-based materials suitable for commercial exploitation, and to investigate methods for the manufacture and deposition of those materials on a commercial scale.”
Silva believes that graphene will be attractive for markets with existing experience of working with carbon-based materials, such as the automotive and display sectors, “and adaptable niche markets in, for example, sustainable energy generation and storage, or microelectronics.”
In his discussions with industry players, Silva has often encountered the question of whether graphene can retain its properties when used in practical applications. His answer is disarmingly simple: “It is understandable that there is some concern. The physics of the situation are staggering when one thinks of the fact that we are attempting to use atomic layer materials to modify and/or protect bulk surfaces over large areas. That is why it is such an exciting, demanding and potentially disruptive technology - if we get it right!
“Large area graphene alone may not be the first material to be exploited. More than likely graphene flakes will be used in combination with other materials, or related materials, such as reduced graphene oxide, which offers some possibility for chemical functionalisation, and thereby solution processability. The ability to use graphene to encase other nanomaterials, such as metal nanoparticles, potentially extends the properties of the materials on their own. But these solutions will not be applicable for the microelectronic industry sectors that will need large-area, high-quality materials from a process such as chemical vapour deposition (CVD), which is one of Surrey's key areas of expertise.”
Silva explains that those materials may be very smart, multi-functional composites. He says: “For example, we have demonstrated that we can encase iron nano-particles in graphene. The graphene protects the iron from oxidation or corrosion, even in nitric acid. It also provides a very large surface area to which functional molecules can be attached.”
Silva cites two main barriers to commercialisation at present. “The first is really that graphene needs some early adopters who translate the excellent academic work to practical applications. Once it gains a critical momentum, other applications will have the confidence to follow. The other is that it needs a sufficient commercial scale. Companies such as Thomas Swan, Durham Graphene Science and Haydale are doing fantastically well to develop bulk materials suitable for early applications that require solution-processable graphene. We will follow their lead with our high-quality, large area CVD-deposited coatings, with a particular end goal of using this solution for microelectronic applications.”