Carbon nanomaterials and challenge driven science

“Graphene is wonderful from the point of view of physicists, but as a materials chemist I will ask ​‘Ok how can I actually use it? How can you get it into applications? How do you get graphene to scale?’” Prof Karl Coleman is a materials scientist who has worked within the field of carbon nanomaterials for over 20 years. His particular interest is in applying carbon nanostructures, like graphene and carbon nanotubes to real world challenges.

Karl reminds us of what made graphene so famous in 2004. It has the properties of being lightweight, strong, thermally and electrically conductive and some very interesting quantum properties. To investigate how to scale graphene, he used a technique that his group had exploited for making carbon nanotubes: Chemical Vapour Deposition (CVD). So rather than removing a layer of carbon from graphite, the same way that graphene was first discovered, Karl’s group decided to make graphene from the bottom up. They would assemble carbon atoms into a graphene sheet.

When they reached the point where they had a reliable method of producing graphene, Karl started a spin out company called Applied Graphene Materials. In the lab if you can make grams of a new material from a research perspective that’s impressive. But when you are dealing with the industry perspective you need to be working within the kilos or tonne scale. The company spent a lot of time scaling the methodology to produce tonne scale graphene.

The next challenge is getting the nanostructure into a state where it is possible to make use of it. For graphene platelets this involves controlling the surface properties and putting it into an aqueous or non-aqueous dispersion, or in a matrix polymer. But there are limitations, once you change the surface of the material you start to lose the very properties you want to make use of. Equally, you don’t often see the same properties in bulk materials as measured in single sheets, but the 3 key properties remain mechanical strength, electrical and thermal conductivity.

Fast forward to today, Karl describes one of his proudest moments as a scientist was when he could see the chemistry that he developed in a lab used in a product that was available in high-street stores for anybody to buy. The work done in his spinout company led to this gratifying moment, of seeing his work in a commercial application.

Graphene continues to capture the interest of materials scientists and industry for its impressive properties. It has become much cheaper and easier to produce in platelet form, and one of the projects in Karl’s lab aims to design a process to make large area graphene films much more economically and readily accessible to all. Instead of using expensive laboratory equipment, the cost would be just a few hundred pounds. He also continues to work on dispersing graphene for use in a variety of applications including coatings and composites. While novel materials offer advantages, these sometimes are offset with downsides, however, combining different materials can often offer a solution. For example, airliners exploit carbon fibre for its lightweight, high-strength properties but it does not offer the desired electrical conductivity, so you need a metal mesh around the airplane to protect it from lightning strikes. This meant that the weight they reduced in using carbon fiber was added back. However, this gave birth to the idea of graphene coatings or resins, that are lightweight and conductive. This promising idea is yet to be realised at scale for commercial purposes, due in part to the rightly cautious aviation regulations.

In terms of applications that we could see soon, Karl describes the focus on functional paints and coatings and composites with the carbon nanomaterial dispersed throughout. Long term he sees the potential of using nanostructures in sensing technology and new electronic devices, where its properties could be advantageous

A vision of challenge driven academic research

Karl joined the University of Liverpool as Dean of Physical Sciences in February 2022 and he describes his vision for the university as doing materials science that has real application in the real world. ​“We want to make materials, advanced materials, and use them in a whole range of applications to offer genuine performance gains. There’s always been a separation between academia and industry, with some crossover. My vision is to get them much closer.”

He explains how the University of Liverpool’s work with KCMC and CPI is part of that vision, to build close partnerships with industry and foster an environment of challenge driven science. This means factors like sustainability, a digital driven society and making applications work in developing, as well as developed, countries would be considered at the beginning of the research and not towards the end.

Karl comments that industry is certainly engaged in what’s going on in research and in universities, and there is the opportunity for nuanced conversations about science. He sees engagement between the two groups as key. Why? Because an academic might think they understand the challenges in the field, but in reality they are not quite what you think. Only when you have those really detailed conversations with industry do you realise what the actual challenges are. As Dean, Karl’s work bridges that disconnect and works to build partnerships between industry and academics, with a free flow of knowledge and ideas and genuine interactions between teams. Part of this work is getting industrial scientists embedded within the department to stimulate and encourage open innovation.

Within this vision there is a necessity for academics to have a greater awareness of impact, and exposure to industry. KCMC’s partnership with University of Liverpool aids the removal of some of those barriers and enables the transitions to commercialisation. There was a time when people may have thought you can’t get high quality science research doing applied research science, but that is no longer the case. The cutting edge of science is driven by the challenges we face in the real world.