AcademiaNet: You're Professor of Nanomaterials at the University of Oxford, where your research focuses on novel nanomaterials made of carbon and/or other elements. How would you describe carbon nanomaterials to someone new to the subject?
Your current research looks at the controlled generation and growth of nanomaterials. Why is it important that nanomaterials are produced in a very controlled way?
At the moment we have rough control of the process to make carbon nanomaterials; for example, we can distinguish between spherical molecules and elongated ones. But the precise atomic arrangement dictates the properties of these molecules, so we need to have much better control of their structures in order to make materials with uniform properties. All C60 fullerene molecules consist of precisely 60 carbon atoms, but there are other fullerenes that contain more atoms. If one adds only 10 carbon atoms to C60 to make C70, the molecule becomes rugby-ball shaped and has different properties.
Therefore, the properties of a nanomaterial as a whole will be governed by the properties of the individual units of the ensemble making up the bulk. For most nanomaterials, these units are not necessarily all identical. It's a bit like if you have a bowl of smarties. The smarties are all similar because they're all made of coloured chocolate, and they all look similar in shape. But if you ask kids, they'll tell you that the smarties taste different because their colour is different. So they've got slightly different properties.
What are some examples of products that might be made with carbon nanotubes once the detailed steps of growth are understood?
In the early days, the ultimate goal was to have precise control of the atomic structure of nanotubes. People were originally looking at using them for transistor applications, and control of their atomic structure is key to controlling their electronic properties. This challenge was so difficult to solve that people started to focus on developing carbon nanotubes to use as fillers in composite materials, because carbon nanotubes were predicted to have outstanding mechanical properties. But the properties of the nanotubes would change so dramatically depending on the production technique. None of the synthesis techniques was suitable to produce the perfect carbon nanotube, so these composite products were not as good as theory – based on perfect, defect-free carbon nanotubes – predicted.
This graph | depicts eight of the different molecular configurations (allotropes) that pure carbon can take: a) Diamond b) Graphite c) Lonsdaleite d) C60 Fullerene) e) C540 Fullerene f) C70 Fullerene g) Amorphous carbon h) single-walled carbon nanotube. Nanotubes can have single walls or multiple walls, but each wall consists of a single graphene sheet twisted into a tube.
One could safely say that the first applications of nanotubes would be something where you would exploit the bulk properties of ensembles of nanomaterials. For example, batteries, filters, displays, or gas sensing applications – anything that involves a composite, rather than requires dedicated properties of the individual carbon nanotubes.
One area you're looking at is in situ monitoring of nanomaterial reactors to observe the processes during production. What are the aims of this project?
The aim of in situ monitoring is to map the local chemistry in a reactor as the growth of a nanomaterial actually occurs, so we can get a precise picture or snapshot of the molecules that form the nanostructures and those that leave the reactor 'un-used'. Getting a better understanding of reactor conditions helps us to increase the efficiency and the uniformity of the final product. It has also enabled us to upscale the processes, making this research more relevant to industry.
In situ work is not straightforward though, because this type of reaction occurs under relatively high temperatures and harsh conditions. Therefore, the equipment suitable to do these types of measurements is not readily available on the market. The only way forward was to build our own device. So, I applied for a grant to the European Research Council to develop our own instrument that would allow us to do this analysis, and from there we started all the in situ work.
You've been involved in science policy in the UK for many years – for example, sitting on a Royal Society working group about nanotechnology – and you've twice spoken at the House of Lords science and technology committee. What motivated you to become involved in politics and policy?
In order to get funding, you need to hit certain buttons with the funding bodies. It's harder and harder to do 'blue sky' research – you have to demonstrate that the tax money you’re using is being used wisely and creates wealth for society. That puts a huge pressure on research scientists to come up with ideas and reasons why nanomaterials are outstanding or why they're going to revolutionise our world.
This issue is almost starting to go into a spin that can be detrimental to the research field. Although impact is important, blue sky research is as important. There is no applied research without fundamental research. We must not forget that most of technologies our lives rely on today are a result of research that at the time was not aimed at a particular application, but was a result of a curious person conducting an experiment to learn and find out how nature works.
I think it's extremely important to talk to politicians and communicate our research to the public, within reason, and let them know what the challenges are in the laboratory. That of course we all want to do research to help make world a better place, create new jobs, find new drugs, but it doesn't happen overnight. Who if not the researchers can say these type of things to politicians? It has to be us, we have to team up.
Dear Prof. Grobert, thank you very much for this interesting interview!
Interview: Helen Jaques