SA Forum is an invited essay from experts on topical issues in science and technology.
Editor’s Note: As leaders from business, politics and science convene this week at the World Economic Forum conference in Davos, Switzerland, to discuss pressing matters of the day, Scientific American is publishing a series of interviews with leading scientists, produced in conjunction with the forum. This is the third of four interviews for the WEF by Katia Moskvitch.
In 2010 two physicists at Manchester University in the U.K. shared a Nobel Prize in Physics for their work on a new wonder material: graphene, a flat sheet of carbon just one atom thick. Konstantin Novoselov and Andre Geim, both Russian émigrés, discovered the material by applying plain old sticky tape to simple graphite.
Graphene is highly conductive and transparent and is also the strongest material known to science. One day it could revolutionize electronics. Novoselov tells us about the possibilities of this 2-D material and how it could transform the industry.
[An edited transcript of the interview follows.]
What does graphene mean for the future of computing?
It is certain that silicon will be used for transistors—semiconductor devices that are the building blocks of modern computers—for at least the next five to 10 years. But people are already thinking about possible alternative materials and technologies to replace silicon when it will fail to deliver for increasingly smaller and smaller transistors. A graphene transistor is one of the alternatives.
I’m also looking into other one-atom-thick 2-D materials that were obtained soon after graphene and at heterostructures based on those 2-D crystals. Potentially they can provide an alternative to silicon technologies, but here we’re talking about completely new architecture rather than just introducing a new material into the system. It’s hard to predict how it will develop because when you introduce one new material into a process, it’s already quite a complicated step, and if you want to change the whole architecture, it requires years of research. That’s why research should start now if we want to achieve something like that in 10 years’ time.
What do you think computers of the future could look like?
Computers are much more than just a display, interface and software: they are mainly about computing power and microprocessors—also known as the central processing unit [CPU], or the “brain” of a computer. In the future, we’ll probably expand the parallel computations, utilizing microprocessors with larger number of cores, when several CPUs will be working together on the same chip, enabling the computer to perform many more tasks with a much greater overall system performance. At the same time more specialized computers will start to appear because the cost won’t be so prohibitive anymore.
Do you think that in the future we will still think in terms of separate entities called computers?
Microprocessors will still exist. You won’t get rid of them. How parallel the computations can be and how many computers will be linked into a large network, into a cloud, that’s a different question. And with advances in telecommunications, with the speed getting higher and higher, it’s much easier to link many computers into a large network. That’s definitely what we’ll see more and more of. We’re seeing it already now, when a lot of our data is stored not on our desktop but in the cloud—and cloud computations will be more and more popular. But the basis will still be microprocessors and electronics and the current architecture.
What else can graphene be used for?
It’s a very strong material that is also highly conductive, so people try to use it for composite material applications as a mechanical reinforcer or to enhance conductivity. A particularly interesting application is in biotechnology, life sciences and medicine, where you can use graphene as a sensor, because many properties are interlinked; change the chemical environment and you immediately get an electronic signal out of it. Something that interests me a lot is the use of graphene as a 2-D membrane. With graphene we’ve got our hands on the thinnest possible fabric and at the same time it’s completely impermeable to any molecule. In principle, we can design it so it would be permeable for some molecules and use it as a biological membrane.
How long will it take before graphene really makes it into the industry and commercial use?
It will be a gradual introduction into our day-to-day lives. A good example is carbon fibers. Only a few years ago we started to see planes where carbon fibers are used. But 20 years ago carbon fibers were mostly used for mechanical reinforcements in sports cars and some sports equipment. So it’s never an abrupt change but a gradual introduction, first from niche markets and then going into larger and larger–scale applications. And that’s exactly what we already see with graphene—some touch-power applications, thermal conductivity applications, mechanical reinforcement, conductive paints and so on—and the range of those products will increase year by year. As we do it, we’ll learn more and more about the material and about the production, so that the production cost will decrease and the quality will improve. And before long it will be quite a ubiquitous material.
Can graphene lead to completely new technologies, something we can only dream of right now?
One of the areas where I work is “materials on demand.” We have a library of different 2-D materials—crystals that are only one atom thick. All of them have very different properties: some are metallic, some are insulating, some are semiconductors, some transparent, some opaque and so on. This library can help design new 3-D materials, just putting 2-D sheets layer by layer—not as Mother Nature intended but combining different materials into a different stack, and this way encoding functionalities as we build this stack. I call it “materials on demand” because, depending on your application and what you want to achieve, you can design this stack according to your needs. We’ve never had this opportunity before—we’re usually stuck with one material—but here we can design new multifunctional materials from scratch.
How will this and other latest breakthroughs in material science transform the industry?
We will bring functionality from the structural level to the material level. So rather than saying that we take silicon and restructure it into transistors to do certain functions, we now say: “Tell us what functions should there be and we will design a material that will have those functions.” It’s a completely new paradigm. And generally the hope is that it will be a multifunctional material—so within a few layers of atoms we will be able to encode the logic circuit, the power unit and so on. You would have a flexible, transparent or semitransparent, multifunctional material that has functions encoded into its structure.
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