Nano – the future for materials development (CRANN)
New materials have been quietly revolutionising daily life for over two generations. Some of the earliest new materials were plastics, which became commonplace about 50 years ago. Plastics now play an important part in everyday life. Their versatility allows them to be used in everything from shoes to ships and from food packaging to fighter jets. However, we have only begun to explore the phenomenally large family of potential materials. There may be materials out there waiting to be discovered or synthesised with properties that we can only dream of; materials that can help cure the most debilitating diseases, materials that can be used to generate clean, cheap energy, materials that can produce fresh water from the sea. The possibilities are limited only by our imagination and our ability to make and test new materials.
In 2004, a new form of carbon was discovered. Graphene consists of a sheet of carbon atoms, just one atom thick. It was quickly shown to have unprecedented properties; for example, graphene sheets have been used to make the fastest transistors ever made. It is also one of the strongest materials ever tested.
However, graphene was initially produced at just one small sheet at a time, a rate that made this material completely unusable for industry. Professor Jonathan Coleman, Principal Investigator at CRANN (www.crann.tcd.ie) and Professor in the School of Physics, Trinity College Dublin and his team have developed a method to take graphite (millions of graphene sheets stuck tightly together) and separate it into its individual graphene sheets. They were able to stop them from sticking back together by coating each sheet with soap molecules, which resulted in the production of billions of soap-coated graphene sheets dissolved in water. Electron microscopy (image shown) allowed them to observe the individual carbon atoms, confirming that they had prepared graphene. Because of its high yield and throughput, this method is ideal for producing graphene in industrial-scale quantities.
Based on Prof. Coleman’s prestigious work on exfoliation of graphite to produce graphene (Nature Nanotechnology 2008, Journal of the American Chemical Society 2009), he has recently been awarded a prestigious European Research Council (ERC) Starter Grant of €1.5 million. The awards are given to only 300 top scientists across Europe, representing less than 10% of those who apply. The awards recognise scientists that are working on research with major potential so that they will have the funding and encouragement to develop cutting-edge technology. Professor Coleman’s grant will help to support his research group for the next five years, which is also funded through an SFI Principal Investigator grant and through his involvement with the CRANN Centre for Science Engineering and Technology (CSET) award.
Looking back to plastics, we can see some downsides. One of the major raw materials used to manufacture plastics is oil – a resource of enormous value, yet a limited one. How can we make materials with less plastic? Graphene is one potential solution. It could be incorporated into any product that uses plastic, making composites which are stronger, lighter and more environmentally friendly than their pure plastic counterpart, e.g., aircraft parts, car parts, sports and household goods.
Two other materials that Professor Coleman is currently researching are bismuth telluride and molybdenum disulfide. Bismuth telluride is used to generate energy from waste heat, for example, from car engines or nuclear plants. Professor Coleman’s method of separating graphene using a liquid process could also be applied to bismuth telluride, which could then be coated onto thin-film substrates and attached to the side of a moving car or a nuclear plant to capture lost heat energy and convert it into usable electrical energy.
Molybdenum disulfide is currently being evaluated for use in batteries. However production of this is currently time consuming and complicated. Using the methods developed by Professor Coleman’s group, it should be possible to produce and apply the films much simpler and faster, allowing industrialisation of the process.
