Imagine a road that always stays ice-free, interacts with vehicles to make their own electricity and has road markings that change according to live traffic. It sounds futuristic but a new partnership between The University of Manchester and Highways England is setting the wheels in motion to make this dream a reality.
Highways England is responsible for the motorways and major A roads in the country, carrying four million journeys a day. All this traffic can take its toll. Adding graphene into road maintenance has the potential to extend a road’s life, increase network performance to an industry-changing level and improve the road-user experience.
Manchester’s Graphene Engineering Innovation Centre (GEIC) is plotting a route to a solution, collaborating with Highways England and Pavement Testing Services to tackle low-carbon and digital road networks, and deterioration of road surfaces in the UK, with the help of graphene.
Graphene – one-atom thick yet 200 times stronger than steel – was originally isolated at the University in 2004 by Nobel laureates Professors Sir Andre Geim and Sir Kostya Novoselov. Mixing graphene with other materials can help the latter inherit its characteristics, improving the strength and flexibility of the original material as well as increasing its heat and electric conductivity, transparency and weight.
“We’re hoping to exploit the range of multi-functions that graphene offers as an additive,” says Dr Craig Dawson, Graphene Applications Manager, who leads the collaboration at the GEIC.
“Graphene can reinforce asphalt making it more durable and extending the lifetime of the roads,” says Dr Arun Raju, an application scientist working with Dr Dawson.
“And you can use less material to do the same job,” adds Dr Dawson. “Highways England were impressed with what Manchester was trying to do with graphene as well as having an interest in what graphene can potentially do in road surfaces.”
Metal surfaces, such as crash barriers and bridges, are exposed to harsh environment conditions and prone to corrosion. As such, demand is high for anti-corrosion coatings to enhance safety, lifetime and reliability. Graphene is a good candidate for this purpose, as it’s light, hydrophobic and highly electrically conductive.
“Highways England are a good role model for other similar organisations. Their emphasis is to produce a product that performs well and costs are acceptable,” Dr Dawson explains.
“Graphene can help to improve safety and the rolling resistance of the road surfaces, which will positively affect stopping distance.”
Graphene can help to improve safety and the rolling resistance of the road surfaces, which will positively affect stopping distance.
Turning up the heat
As roads heat up significantly and stay hot for a long time, there is the potential to utilise them for interseasonal heat transfer.
“Not only could we see large benefits in the mechanical properties of our roads but we could also look to induce electrical conductivity which could be used for melting ice on wintry days. We could also look to improve the thermal conductivity and heat dissipation by capturing solar energy through the road surface and storing it to be used in colder conditions.”
This process requires embedding water pipes below the road surface which capture the solar energy in summer and recirculate it in winter for de-icing and snow removal. Adding graphene to the roads will increase their conductivity, leading to a more efficient heat transfer of the harnessed solar energy. In addition, the road’s temperature gradient from the surface downward can also be used to generate electricity. Graphene can dramatically improve the efficiency of energy conversion.
Steering the way
The GEIC specialises in the rapid development and scale-up of graphene and other 2D materials applications. It’s an industry-led innovation centre, designed to work in collaboration with partners to create, test and optimise new concepts for delivery to market, along with the processes required for scale-up and supply chain integration.
Walking down the corridors with Dr Dawson, we look at the state-of-the-art laboratories and facilities that are inspiring success in commercial endeavours.
“We will put graphene in bitumen and perform tests. We should have asphalt samples with graphene before Christmas. Hopefully from there we will get a small section of road or pavement from the local council for real tests”.
“We have access to the entire supply chain. We can rapidly develop products and technologies and push them through to a practical use,” he explains. “We’ll see if graphene from a particular supplier is suitable for specific applications. If not, we’ll look for another or modify an existing one,” adds Dr Raju.
The GEIC, along with the National Graphene Institute and the wider advanced materials community at Manchester, is playing a part in Graphene City, an ambitious project to realise graphene’s vast potential, creating a knowledge-based economy and bringing innovations to the market.
And as collaborations like this show, the benefits of Manchester’s graphene expertise will stretch beyond city limits, across the UK and beyond.