Graphene science | Mikael Fogelström | TEDxGöteborg

new materials have always been a bearer of new technologies and subsequent sub societal societal development and advances the most simple examples we go back in history and think about the Stone Age which developed into the Bronze Age and then it went on into the Iron Age and each age is labeled by the material that was was bearing the new the new technology on or the new society at us as a whole and every new material was better than its predecessor and it also made life simpler for the people of that age I think in the beginning it made life bearable just to to exist and that's it and this is the way it has gone on in in our society and still today we always have new technologies that come with the introduction of new materials or substances there's a new development that has come only in the latest decades or so and that is the ability of using basic sciences like physics chemistry combined to material science and we are able now to atom-by-atom design new materials with designer functionalities and today I'll talk about the ultimate material which is actually not designed but it has been there all the time and you see a picture of it and you have been playing with it since you started to use a pen and doing the calligraphy that we just heard about so it's all about one layer of atoms that are and it's known as graphene and this is what I'll try to spend a couple of minutes of your time to explain graphene is amazing it's the material of superlatives it's best in everything this is what we are told of course these days this is a truth with modification and it's a truth that has to be verified but still today when we think about it it's only one atom thick or thin how you want to put it and this is a material which theorists like I have said this is impossible any thermo dynamical fluctuations will curl it up and you know when you're in a hurry and you take your glad pack and want to cover something and it all curls up this is how it should behave but then these guys in Manchester and the Guymon Coast and over Salem said ok this is impossible let prove them prove them wrong and just try of 10 years ago they published results showing that you could actually make useful things and address this single layer of atoms this material is the strongest material we know it's stronger than diamonds diamond isn't stable it will fall into graphene if you just excite it with a little bit of energy over a threshold so graphene or graphite is actually the stable form of carbon and being the strongest it's still flexible and now being the strongest one wonders what would you do but if I had a hammock of graphene here then I could put the baby and it would rest in thin air in your eyes it's not that I could put a truck but a 4 kilo newborn child it's another issue with another property which is nice and that is that it has a width a length but it has no height so it's only surface so you can address it all over so you have this big sheet which you can work with and then it's strange in that sense that I can put any material substance on top of it and it won't lap it let it through its impermeable to other elements and substances and being so thin if you take the amount corresponding to a bite of a Snickers bar that's 10 grams roughly you would cover three fields of three football fields of graphene we we made a calculation it I'll talk about it going into electronics if you take 15 kilograms you cover all the displays computer displays iPads whatever with graphene it's something that I could carry along that's the world production it has other properties it's the best thermal conductor it carries heat extremely well it's one of the best electrical conductor it carries charge extremely well and on top of this it's transparent so it lets light through and what one has seen is with all these superlative properties you can probably make quite a lot of interesting things out of it and this is what I'm going to try to dwell on a little giving you some examples and also showing a little bit a little bit what me and my colleagues are doing up at Chalmers nowadays but first I thought I'll give you a crash course in science and if you take the picture here to my left you see a chicken wire with black spots in the apexis where them the lines meet that's the carbon atoms and they organized like this by themselves and the reason why they do that is carbon has the possibility of making a lot of different compounds and it has four electrons in its outer shell which are responsible of it is very easy it's with these nice blobs that I have shown here what happens is three of them will fall in a plane make something that chemists would tell you it's sp2 hybridization and the neighboring carbon atoms want to share electrons with it each other and they do this very well it's a covalent bond it's called and this bond is extremely strong this will make graphene the strongest and also flexible material that you have so the chemical properties comes from this simple L bonding and then we have the blue guy which is the electron which is left and YouTube's quantum mechanics it doesn't know if it's on top or bottom because you have some uncertainty as you should but this electron skates around this chicken wire with the speed of light in that material so it's basically a relativistic particle it has no mass so it was a big excitement of course that now we can do really test fundamental physics in this material and this blue guy is responsible of the heat carrying the electrical charge and also the transparent and now of course you can start playing around combining properties or exploring special properties as far as you can and this is something that we know of as translational nanotechnology and I show you four examples and I'll go into three perhaps a little bit in more in depth the first one you see up in the left corner is the possibility of making flexible transparent electronics and this is a bit of science fiction I would take up a roll of plastic it would look like it's transparent and I'll get today's news of whatever I am subscribing I'll get a movie I get whatever so you can have a piece of material which is flexible and still communicating so it's just a new way of communication and information processing so ICT that's information communication and technology basically that's shot for that we have another one which is down in the corner and you see an airplane there and as graphene is so strong you can put it into composites and it's not only strong it's extremely light and this is quite important because now you can make big big chunks of this material and put it in to let's say the body of an airplane you cut the weight by a lot and the fuel costs will go down and you can just do other kinds of vehicles basically up in the right corner you see a face of a small car which is plugged in and we all know about that we want to have electrical cars too whew all the emissions and so on and graphene is is essential in that because it has promise of making very effective batteries and super capacitors that batteries that load very quickly there is an idea of having super capacitors to drive elf snug and you know the lube boat going across here basically every time it docks fueling up with electricity and shooting back and flip fueling up again nowadays you know that if I want to take my iPhone or my car I need to spend hours to get it loaded now you could do it in a few minutes and then one thing which is very interesting you see the picture here you see a DNN strand strand is going through a hole which is made in graphene and the idea here is that pulling it slowly through the graphene mesh you could sequence the DNA and understand more there were four scientific articles that came out the same way they same week with the same kind of picture so what has happened with this is basically its imagination is the limit but we still need to prove these things now I want to say a little bit in depth about graphene and here's something that came earlier this year from a group in Germany and they were playing around with graphene transistors in a liquid and they realized that they could operate them and and make them interact and of course there's a big problem let's say your eyes destroyed for some reason but yes your visual cord is still working then you would like to connect that to something biocompatible and give it impulses because one knows that it you you can you can regain sight in a sense and and today you do this retinal retinal transplants but in this idea graphene seems to be biocompatible which means that if you let graphene interact with a nerve cell it will meander out and it's ready to take the electrical impulses that you can feed it and this you would do by placing a camera just like the CCD camera would which would give the impulses due to the to the graphene membrane and then it would trigger impulses for this another important thing in today's society it's interesting it's important but it's extremely problematic that's our need of having vehicles to get around and this is a concept car there have been many different concept cars always around to solve different problems but this one is now very integrated and its idea taken out by Daimler in this case but there are others and it's this smart car you already today if you go to Berlin you see them like we have our bikes in your body they have their cars that you can subscribe to and drive around very interesting but this car now you have integrated you have make that made the chassis of a composite material you have made the roof smart materials so it's like a solar cell so it's picking up energy from the Sun which is feedback to its graphene-based battery which is is driving it so it's fueling us it's going and of course you can always top off quickly at some station and it also could have smart material in it because you could have transparent electronics so your windscreen would be your display board and so on so there are a lot of these ideas which are which are working on going in this direction I have a third example which I think is extremely important because this is perhaps one of the big sources of war today water what to supply we have a lot of water but 98% of it is too salty to use so people have think thought okay let's desalinate it take away the salt turns out that this is a extremely energy inefficient and hard process to do and it's slow now this is based on a computer simulation where you have a divider of graphene where you have made none of holes in it which and you have decorated the holes by by hydroxyl hydroxy molecules and you apply a pressure gradient so it's reverse osmosis and what you have to to to the right is saltwater and this little hole is selective it's that's only they be the water through and leaves the salt on the other side and it does it to a hundred hundred two thousand times more efficient than any other any any other processor process in this kind of in this field what I have told you about now is great possibilities and of course they are still this is a computer simulation there's no experiment yet and and the car doesn't exist and there was only idea but that the potential of this material has allowed the European scientists to go together and actually get the big funding from EU on the on the level of a billion euros over ten years and how it was sold to them is this funny picture I hope you don't start reading now but the idea let's focus on the color scheme here to the left you have the idea of science you have this fantastic material of superlatives you have the bright ideas of designers engineers and etc you have other materials once you have proven that one is possible to do two-dimensional you can have more and the idea what is said that we want to take this and we want to be able to compete to Asia and there and Americas and so on and go together because you have to make this a joint effort and the idea is that we want to take this material over ten years from the blue to the red and that means going from academia into industry and of course you can sell it on making faster computers ICT and so on and you can have energy and all these important things but the important most important thing when you pick the mind of the guys in EU is that we bring people together we make societal changes giving job opportunities education and actually working together this was what they were interested in ask them what should I tell you in five years and they saying well it wasn't so important that all the big games in technology of course they're important but but it was this that we could work together because we are 17 countries they're of close to 200 groups working together ok that was a little bit about visions and so on let's talk a little bit more about how its produced there are several ways of producing graphene the first one you heard about is you take some tape you take some well define graphite and you start ripping it apart like this take six rips and you have graphene even the King can do it anyone can do it under guidance it's extremely easy but you need a microscope you need to have the ideas and of course and then you have to find it that's very hard because you get a square micrometer micrometer of this so you have to find it so of course we want to make high-speed electronics so you have to do this you have silicon carbide and you evaporate the first layer of silicon and you get very nice compatible with with with electronics industry and in fact in lynn shopping within our projects we have the first graphene producing company in sweden you have down in the right corner you put graphite in liquid and you shake it with ultrasound and it falls apart and this you can print then you make printed electronics which is superseding any printed electronics today the thing that my colleagues do in at Chalmers is known as chemical vapor deposition that means that you put a hot copper plate or some metal in a furnace and you introduce carbonate gasses and that those dissociate and the carbon falls down on the metal and by self-termination it makes a single layer of graphene and the guys we are sort of competing with in the Asia already made 100 meters 20 centimeters apart and of course this is now possible for all kinds of applications what they do in our cleanroom is they make the graphene by the CVD they use a process which is close to a battery process to bubble off the graphene and then you see a picture of a typical size of protein it's limited in our place by the size of our furnace but in principle I used to say that all these fantastic things we're going to do with this size of my thumb so we need to scale up a little bit as you understand but the idea is this we can make the graphene and we can now go on and into our research this is also too busy please don't try to do it understand everything of this picture but the essence of this picture is that we have groups that are making vertically emitting lasers for communication purposes you have fiber to your homes some who don't live too far away from urbanization but but you know you need to use light for communication and they're making these lasers and one of the basic properties is this that they need to have they need to have a transparent current spreading electrode and this and there is where we try to see the properties of the graphene that was made and they feed it back and they feed back to the process and we learn all the way how to do it but this has even more consequences because transparent electronics today is done with one of the scarce materials indium in indium tin oxide so I mean I guess we had some polls in the previous talk but everyone raised their smartphone we all have it and there's an enormous demand because everyone in the world wants to have it and and it's really one of the most scare materials that you have so the promise of this basic research is to work towards trying to replace something that everyone wants to have and we all know that iPad is great but it's not flexible because graphene would be possible to make more more alternative functionalities and shape and form of this and if you compare indium 10 indium is the fourth among the 14 rarest it but elements and carbon is the fourth most abundant so we have a lot of possibilities here ok so coming back to where I started I hope you've got some kind of flavor that in this simple pencil drawing where you actually have produced not graphene but probably quite thin layer of layers of graphite actually could hold a promise for the future you

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Keywords: ted talks, Chalmers University Of Technology (Organization), Graphene Science, ted talk, ted x, tedx talks, one-atom thick carbon structure, TEDxGöteborg, tedx, Mikael Fogelström, André Geim, Graphene (Invention), ted, TEDx, tedx talk, Kostya Novoselov

Id: eh3dA8xnZ4Y

Length: 19min 59sec (1199 seconds)

Published: Sun Jan 12 2014