Sensitive matter: why graphene has not yet become mass-produced

Sensitive matter: why graphene has not yet become mass-produced

What are the present-day challenges of scientists exploring the properties of graphene, British scientist having Ukrainian roots, Leonid Ponomarenko, shared his thoughts with Innovation House.

In 2010 Andre Geim and Konstantin Novoselov from the University of Manchester (UK) received the Nobel Prize for graphene material properties studies. This is world’s thinnest material, it has electrical conductivity and is strong at the same time. In theoretical terms it could make revolution in the world of electronics, and not only there. Thin flexible displays, universal devices – when smartphone turns into computer and vice versa, solid body armors and means of protection – media outlets used to write about every possible application perspective.
Доктор Ланкастерського університету, фізик українського походження Леонід Пономаренко
Ukrainian-born Dr. Leonid Ponomarenko of the Department of Physics at the University of Lancaster worked within the “Nobel” group. Currently he cooperates with the National Graphene Institute, opened in 2015 in Manchester. It is aimed at speeding up the commercial usage of this material. The Institute has more than 60 partners – companies from the commercial sector. Airbus, Syngenta, Tetra Pak, Siemens are among them.

At the invitation of “Vodafone Ukraine” Leonid Ponomarenko met with journalists and told Innovation House why for so many years graphene has failed to become mass-produced.

The “Nobel” team

I knew Konstantin Novoselov even before he discovered graphene. We had postgraduate training program in Holland at one time, but in different universities. I used to come to his university and we made experiments together.

Then he went to Manchester University. I was just finishing my postgraduate training program. He called me and asked what I was going to do next, and invited me to be interviewed.

As a matter of fact, there were no interview. I was given specific task and I was told: “Here are the samples, here is equipment. You have one week to do the work. You do it – work is yours. You fail to do it – no offense”. I was given graphene and atomic-force microscope, which I saw for the first time ever. The task was rather difficult and I coped with it literally a few hours before my departure. I’m not sure that I would not get this job if I failed this task. Frankly speaking, I do not know exactly what was the purpose of that task.

In speaking of University of Lancaster, it existed on the graphene study map even before I got there. The theory was being developed there foremost.

There was a group of smart theorists. The smartest of them, Vladimir Falko, soon became Director of the National Graphene Institute in Manchester. One can say that we switched our jobs. The only thing is that I moved to Lancaster to develop the experimental part.

I am the scholar of The Royal Society – analogue of our National Academy of Sciences. Any emerging scientist may go there, and if the project is good, he has a chance to get this scholarship. Any university is ready to employ the scholar, since Society pays his salary. At the same time Society ensures that the person is not overloaded with pedagogical and administrative work. For him to be focused on scientific activity. Therefore, I do not give many lessons.

The biggest problem

One of the biggest problems that is currently slowing down the commercial use of graphene, is the rather high cost of its creation.

Much is being done to make its production cheaper. Europe has a large program called Graphene Flagship that was started in 2013. The idea is to get graphene out of the laboratories to the manufacturing site. Theoretical funding of the program – 1 mln EUR for 10 years, this is the ceiling value. But this funding shall first be gained.

There is a number of ways to get graphene. At very least, I know five or six. And all they make material of different quality.

High cost of graphene creation slows down its commercial use

One may produce graphene on a wholesale scale, several square meters at a time. But the quality of such material will be very low (it will not be monocrystals, but polycrystals instead).

High-quality material may be produced almost “manually” and in very small quantities. The easiest way is to get it from natural graphite using the adhesive tape, even though it sounds funny. If was obtained this way for the first time, and this is how we currently get material for our studies. I use high-quality graphene with monocrystals, the size of which is about 20 microns.

What is already being done from graphene

Low-quality graphene is completely suitable for some practical applications. For instance, it is used to produce ink. Printer is filled with the ink, and you may print simple electrically-conductive electrical networks on any surface. Microcircuits, but with no active components. Active components, namely transistors, are not produced from graphene, though progress is being made.

If you combine graphene with plastic, you’ll get very solid plastic

Moreover, low-quality graphene may be used to manufacture composite materials, namely combinations of graphene with other materials. With plastic, as an example.

Graphene – very strong material, if it is combined with plastic, we shall get very solid plastic. But in a real-case scenario this idea does not work. After all, to make the plastic stronger, it shall “hold on” to graphene. But it slides off. This problem shall be resolved: to “attach” some molecules to graphene that would help it to hold on to plastic.

Therefore, there is such a material – graphene oxide. It is so called, but actually it is not oxide – it composes of both oxygen and hydrogen. This is disordered structure, in which molecules “stick” to graphene in a totally random way. Disadvantage of this material, as compared to graphene, is that it is insulant. Advantage – it is easier in operational behavior, chemical compounds are easily done with it. Including, combination with plastic. But such composite materials have not yet received their commercial applications.

Speculative activities around the graphene

As I noted before, a lot of people study graphene properties. Results of these studies are being published in an increasing number of scientific journals. However, you cannot always trust them if they are not Science or Nature magazines.

And you know what? There was an article, several articles, in which antibacterial properties of graphene oxide were studied. It was said that if graphene oxide is added to the solution with bacteria, it will supposedly kill bacteria. But in fact it was later checked, including in our National Institute of Graphene in Manchester. If you properly set up this experiment, you will hardly ever notice these properties. Though there were rather good pictures published in magazine, they showed how graphene oxide cuts off these bacteria using the “nanoknives”. This was published in all seriousness, and journalists picked up this topic. Reviewers of such articles cannot check the experimental result. Therefore, they look at qualifications of persons, how the experiment was set up, whether idea is interesting, and whether it makes any sense at all. That sums it up: as if well-qualified persons wrote an article, and we obtained such a result.

Actually, there is a science for this – for you to believe. But hype went down, people became interested in the topic. And it turned out that this works not exactly this way. Despite the fact that some groups of scientists repeated this experiment and partially confirmed it, I tend to trust National Graphene Institute more.

There is another problem with publications in media outlets, and I personally have faced with it. For instance, some scientific article is published in Nature or Science. Scientist communicates with journalist and tries to explain him in lay terms. Sometimes scientist is good in it, sometimes not bad. But the fantasy of the journalist is activated, and he writes some little extra thing at some place. Then this publication is seen by other journalists, and they dream up a little more. In such 2-3 steps, the initial information becomes so distorted that it hardly lines up with reality. There was a case when the original article dealt with calculations. It was said that if holes are properly made in graphene and if graphene is properly shaped into three-dimension structure, then in some cases it becomes much stronger than the two-dimensional one. But these were theoretical calculations. However, eventually media outlets presented this like a new form stronger than the diamond was discovered.

About cooperation with Ukrainian scientists

The more I study graphene, the more interesting it becomes. One of the research lines that grows rapidly – combination of graphene with other two-dimensional materials. As a result, heterojunction structures are being produced – basically, three-dimensional materials, where the engineer decides by himself what layer shall be applied and in what sequence.

Hundreds of scientific groups all over the world study graphene

Hundreds of scientific groups study graphene. I am in the constant contact with five or six of them, it’s about 20-30 employees. Just for the record: sometimes it’s even difficult to keep track of everything that happens in this field.

I do not communicate much with scientific groups in Ukraine. Ukrainian science is too small, and there is outside chance to meet someone.

I admit that I keep in contact with Ukrainian physicist Sergei Sharapov. But so far we have no joint projects. In other words, we do not cooperate with Ukrainian scientists.