Graphene is one of the most important discoveries in physics this century.
And according to those at the heart of its development in the UK, it is poised to revolutionise almost every industry, including construction.
Graphene was first identified 12 years ago by Andre Geim and Konstantin Novoselov at the University of Manchester, during what they dubbed “Friday night experiments”. Though graphene had been theorised about since 1947, it was not until a “piece of sticky-tape” was applied to graphite and then ripped off, leaving flakes only a few atoms thick that the material was physically identified.
The part-genius, part-serendipitous discovery is indicative of the approach Geim applies to the scientific process. “Human progress has always been driven by a sense of adventure and unconventional thinking,” he said on receiving the Nobel Prize for Physics in 2010.
The truly extraordinary nature of what the two scientists discovered is still being investigated. The two-dimensional, atomic-scale honeycomb lattice has a variety of seemingly conflicting properties. It is the thinnest material on earth, but stronger than steel. It is ultra-light yet immensely tough and, though permeable to water, it acts as a barrier to the lightest of gasses.
Such an array of different qualities offers myriad possibilities for use in the construction industry. At the moment, however, it is a struggle to find anything that uses graphene on the market. You can currently buy a light bulb made 10% more efficient by a graphene coated filament, and Andy Murray used a part-graphene tennis racket to reach world number one this year.
Graphene exfoliation jpg
“Graphene as a material is still relatively young,” says National Graphene Institute (NGI) business director James Baker. “Twelve years is not a lot of time in the life of a material. If you look at other materials, like carbon fibre or silicon, typically it takes 25 to 30 years before they can be widely commercialised.”
Though not yet a teenager, the excitement around the material has attracted massive investment from the UK government and Europe. The NGI at Manchester cost £61M to set up and was funded by a mixture of government and European Union money. By 2018, Manchester will also be home to the Graphene Engineering Innovation Centre (Geic), also partly funded by the UK government.
The hope is that investment in the research of graphene and other 2D materials will allow the University of Manchester to create a knowledge-based economy in the material’s birthplace. Baker believes that the Geic and the NGI can help move graphene from the research stage into commercialisation quicker than would otherwise be the case.
“A prime aim of the institute is still to fundamentally support research,not just of graphene but a whole family of 2D materials. Another aim is to try and progress along those first phases of commercialisation,” says Baker.
The NGI employs a method known as Technology Readiness Level (TRL) to gauge the maturity of a certain technology. The TRL scale runs from one to nine, with nine indicating a technology that is proven to function in its operational environment.
JW National Graphene Institute Visit 1
“Most universities focus around levels one, two and three,” Baker continues, “the purpose of the institute is to accelerate those TRLs to four and five.”
Public sector funding alone will not enable graphene to move from the research stage toward commercialisation, and the NGI works with a number of commercial partners, from Rolls Royce to Siemens. “Part of the challenge is engaging bigger and smaller companies, start-ups and scale-ups.”
The construction industry has something of a reputation for being risk averse when it comes to investing in new materials. Despite that, Baker says there has been some interest from some companies involved in creating infrastructure materials.
“We have had some interest from people like Tata Steel and Morgan Advanced Materials. So it is the big companies, the supply chain companies. But part of the challenge has been getting people to engage because it is quite early in the life cycle.”
Baker believes that some of graphene’s properties make it particularly attractive to the infrastructure sector: “Two hundred times stronger than steel – who in the construction industry would not want a material like that?”
We are seeing an increasing involvement from the construction industry and others.
National Graphene Institute business director James Baker
The most immediate future for the material in infrastructure probably lies in adding it to pre-existing products. “You can add graphene to a polymer, a resin, a concrete or a steel to improve its properties and we are currently starting to engage with a number of people from construction. For example, we are looking at treating bitumen with graphene, and we are engaging with a number of ideas around concrete.
“So it is still initial feasibility-type work, like sponsoring a PhD, rather than large scale multi-million pound investments. However, we are seeing an increasing involvement from the construction industry and others.”
Though still very much in the developmental stage, it would appear that the potential uses of the material in the construction industry are not all that far away. This is quite remarkable considering that 12 years ago, the material was thought impossible to isolate.
As interest in using graphene grows, so does the need for a high quality supply of the material. The idea that anyone could extract the allotrope themselves with a piece of sticky tape and a pencil lead is an exciting one, but as graphene manufacturer 2D-Tech’s chief executive Neill Ricketts points out: “You can’t make a lot of money doing that.”
2D Tech is one of the leading manufacturers of graphene in the UK and also works to develop new graphene-based products. Ricketts is similarly positive about the possibility of graphene being used in construction, pointing to the “huge amount of work being done on how graphene can be used as a reinforcer for concrete.”
We cannot produce enough and we are doubling capacity on a monthly basis.
2D-Tech chief executive Neill Ricketts
They use a patented mechanical and chemical exfoliation system, to extract graphene from graphite. As Ricketts elaborates: “We mix graphite, a naturally occurring commodity product, with a special ingredient, then we use mechanical force to split the sheets of graphite into graphene, then we produce very specific high quality graphene for a whole range of products.”
“We currently produce about 500g a week, though we are in exponential growth at the minute, we cannot produce enough and we are doubling capacity on a monthly basis.”
That demand is expected to increase enormously, and Ricketts suggests that “by 2025 we could see worldwide capacity needing to be in the order of about 54,000t.”
The economic feasibility of graphene is still compromised by the cost it currently takes to produce the material. “The only issue is the amount of graphene available and the commercial price point,” says Ricketts, “currently 1g of proper graphene would cost in the order of £400, which is obviously not sustainable for mass production… it will probably just take a little bit of time to build the capacity and get the commercial model to work.”
Despite the caveats, the benefits graphene may hold for infrastructure are becoming evident. A PhD thesis published in 2014 detailing the reinforcing effects of graphene oxide (GO) – a similar though less effective material – on Portland cement paste suggested that the compressive strength of the paste is increased by 46% when GO is added. Meanwhile, the effect graphene can have on steel is just starting to be researched.