Nanotechnology Expert Explains One Concept in 5 Levels of Difficulty | WIRED

hi i'm george celevski and i'm a research scientist at ibm tj watson research center today i've been challenged to teach one concept and five levels of increasing complexity and my topic is nanotechnology nanotechnology is a study of objects in the nanoscale between one and a hundred nanometers in size and it turns out that objects in this size scale have really interesting properties that differ from objects at a macroscopic scale our task as nanotechnologists is to understand these materials understand their properties and then try to build new technologies based on these properties at the end of the day my hope is that you'll understand nanotechnology at some level [Music] hi are you bella yes bella i'm george nice to meet you nice to meet you i'm a research scientist do you like science yeah i wanted to talk to you about a specific type of science called nanotechnology have you ever heard of this word before nano's kind of a funny word right it's a word that's used before another word and it means one billion what's the smallest object you can think of a baby ant a baby and very good so i have over here a meter stick let me show it to you and so that's a meter and if i divide it by 1000 i get a millimeter so milly just means one thousandth there's all these little lines on the ruler and each of those little lines is one millimeter so baby and is probably a couple of millimeters so even the thing that's the smallest thing you can think of it's a million times bigger than a nanometer tiny tiny tiny tiny tiny tiny if i took this stick and i was to draw one billion lines the distance between those two lines would be one nanometer so that's really all it is it's just a measure of size but it's really really really tiny you know smaller than anything that we can see with our with our eyes the reason why in nanotechnology we you know in scientists we care about things that are that small is because there are objects called atoms have you ever heard of atoms before yes um i first heard of them on a show i watched called storybots they're just little things that make up like everything on earth even earth that is a perfect explanation but what if i told you that scientists invented a special type of microscope that not only lets you see atoms but also lets you move them around and build things with them would you think that would be pretty cool yeah so it's called a scanning tunneling microscope and not only can you see the atoms but you can move them around atoms are kind of sticky you can actually build things using this instrument with actual individual atoms so if i gave you that machine would you want to make something would you want to look at something very carefully i would want to make a unicorn have the atoms you are definitely a second grader my daughter would probably answer the exact same way a unicorn would be awesome why do you study stuff so small i study it because objects that are that small have really interesting properties they behave completely different than objects that are big and because of that we can build really cool things with them like really fast computers for example or new types of batteries or new types of solar cells and a lot of nanotechnology is kind of like playing with legos you take these small objects and you you put them together to build something new something interesting that no one's built before it's like legos for scientists cool so how old are you i'm 16. 16. so what is that you're in 10th grade junior year so 11th grade so have you heard of nanotechnology have you heard of this term before yeah i've heard of it what do you think of when you think of nanotechnology it kind of seems very science fiction you know you're right when you read about some of these technology it does feel like science fiction but the part of nanotechnology i wanted to talk to you about is stuff that you probably use every day most of your day all of the time can you guess what aspect of our technology i want to talk to you about my phone yeah so modern computer chips rely heavily on nanotechnology does this look familiar to you can you guess what this might be i don't know so this is a silicon wafer and they're embedded in basically almost every object that you use from a laptop to a phone to cars television sets appliances we end up cutting these into little squares and those repeating patterns each of those is a processor and those chips are what goes into all of these objects what i want to talk to you about is how we got from kind of where we started and how we're able to actually fit 18 billion of these little devices in a little you know one inch by one inch uh area they're called transistors it's a switch very simply think of it as a light switch that turns on and turns off using an electric field by applying a voltage i went through my kids lego bins to build a very simple model of a transistor and these are wired together in circuits so that you can do computation you can do logic with them where nanotechnology comes into play the way you double the number of transistors on a chip can you guess what you would have to do to this transistor you make it smaller you have to make it smaller exactly but here's the problem so about oh 10 to 15 years ago the devices got so small that if you shrunk them this gate that actually turns it on and off loses its ability to control the channel and so they did was they took devices like this into these things we call them finfets kind of like a fin on a fish so they're very thin transistors the width of these fins is only six nanometers okay so six nanometers is 25 to 30 atoms across and they repeat this over the entire wafer just about perfectly it's just a huge feat in engineering but these types of devices are exactly the kind of devices that your phones and computers either have or will have in the near future and it's a way that nanotechnology is directly impacting you right now how do you make stuff that small like obviously it's not handmade so is it like factories and stuff exactly so these are made using a technique called lithography you basically cope the silicon wafer with a polymer then you put a mask on it and then you shine light through it and the features of the mask the size of those holes determine the feature size in the chip it's not just the size of the mask that matters it's the wavelength of the light that's used we talked about nanotechnology being science fiction before but this is real stuff that's being produced that's being made that's being used every day by people in middle school i've built all the like the little switches where you turn the electricity on and it goes from like one thing to the other but those are like the really big like comical like plugging in like legos and stuff when we saw the picture of all of the little ones like it's like a city it's crazy how simple and complex it is at the same time exactly i couldn't put it any better that's right [Music] so what's your major chemical engineering what made you choose that like any freshman going into chemical engineering i was like i like chemistry so i'm gonna go into chemical engineering but luckily i also like you know all the math and all the science too so have you taken a quantum mechanics course i have i took that last year i think to really get deep into nanomaterials and nanoscale devices you really have to understand to some level quantum mechanics what it teaches us as we make these devices smaller and smaller their properties begin to now depend on the size and the orientation of these devices there are materials and you're taking a 2d materials class you know about this that are intrinsically thin like as they're grown as they're fabricated they're already at the nanoscale and they possess these quantum confinement properties that as a nanotechnologist you try to exploit and so the first ones i wanted to talk to you about are quantum dots have you heard of quantum dots before yes so these are typically semiconductors they can be cadmium selenide cadmium sulfide zinc cell not and they're small clusters of atoms they can be from two to 10 nanometers what's interesting about these materials well the other day we were talking about the kind of different dimensions you can have of nano technology so all the way from like 0d to 3d if i remember correctly my professor labeled it as 0d that's correct yeah because of quantum confinement once you get below this 15 nanometer range the band gap of the material depends completely on the size of the material so in bulk materials if you want to change the band gap you have to change the material right but in these quantum dots specifically just by changing the size you can change their band gap and because their band gap is changing their optical properties are different and you can precisely tune the wavelength of light that they emit just by changing their size what are the applications of these quantum dots there are people that are exploring using these materials for diode lasers there are companies that are building displays from these materials and there are even people thinking about if i take these quantum dots and i change the chemistry on the outside so they stick to specific types of cells or tissue that i could really do some interesting imaging and therapeutic work to track disease even maybe to treat disease if you can very precisely control the chemistry how far away is this from being actually used on an industrial level the optical applications are in development the science has really been worked out the health stuff because of all of the things you have to consider when you're putting something in someone's body is definitely further out there for example some of them are made from cadmium cadmium's toxic you would never put that in someone's body but there are other materials like gold and silver and titanium dioxide which are less toxic and people are exploring using those so have you learned about graphene yeah do you know what this is carbon nanotube carbon nanotube right so if you roll up graphene depending on how you roll it and the angle you roll it with it has different properties so if i roll it one way it'll act like a metal if i roll it a different way it'll act like a semiconductor the one that gets everyone most excited is that the electrons and holes move very fast through through graphene and so there's a lot of interest in using these for certain types of high speed electronics the other interesting application is because it's one atom thin it's very sensitive to changes in the environment and so there's a lot of interest in using them as diagnostics it's on us researchers to find ways to a control that process and then be to actually build some sort of interesting technology from them so you've been talking about the different ways you can say roll these nanotubes so how do you go about building and controlling these nanotubes in terms of their diameter so you're you're speaking my language this is what i spent many years of my life working on you don't physically roll up graphene you grow nanotubes by basically taking nanocrystals and you deposit them on a surface and then you do a cvd process chemical vapor deposition so you basically flow in a carbon source the carbon dissolves in a nanocrystal and then once the nanocrystal is saturated the nanotubes precipitate out of them in tubes then you have to develop ways to go into this pile of nanotubes and pull out exactly the ones that you want so i have to find ways to program them to go exactly in the places that i want i modify the surface of the nanotube with specific molecules that recognize one type of surface over another and then i just pattern the surface and the tubes just land exactly where we want them to and it's still very much in the research stage the ultimate goal is to build functional high speed electronics using these these new materials in my nano materials class actually just a couple days ago we were talking about different applications of nanotechnology and things we know and we touched on the topic that right now silicon is kind of down to the smallest level that it can get and so we have scientists out there researching other materials drilled by silicon yeah 100 that's right and that's the motivation for looking at these emerging materials but i would never bet against the innovation and the creativity in this nano electronics space tens of thousands of scientists every time they hit a barrier at least historically as a guy they have found a way to overcome it i mean it's a real marvel in ingenuity so i gotta ask the lights that are behind you is that related to the quantum dots that you work with at all it's just pretty lights but now that you suggested it these were inspired by the array of quantum dots that we showed earlier so that's the story i'm going to stick with i like it well thank you so much this was all so very interesting so you're a graduate student and so tell me a bit about your work i'm working on energy storage materials and the most popular uh our batteries that we work on a lot of the revolution that's come in electronics is kind of our model to try and use some nanoscale advances and put them in uh to batteries what is it about nanomaterials that scale and the properties of these materials that make them uniquely promising to incorporate into battery technology so for batteries one of the main constraints when we're designing batteries is trying to maintain or reduce the volume and mass of the components and nanomaterials are particularly well suited to adding functionality while having this negligible increase in volume so we get a huge benefit from using nanomaterials without sacrificing the volume of the battery what is it exactly that you're trying to tease out of these materials to improve the battery's performance at first one of the main things that we did was use nanomaterials to add conductivity and so carbon analysis and graphene are really good at adding conductivity to batteries and then in the subsequent years nanomaterials have been really interesting from things like incorporating sensors into batteries so increasing the functionality of batteries having some responsive materials that use things like graphene sheets that are incorporated into a matrix and then you add a safety functionality to a battery we're trying to squeeze out almost all the functionality that we can and as new nanomaterials are being discovered in their new properties being discovered a lot of the time that that someone tries to think of a way to translate that into a battery because the materials are so small they're at the nano scale their properties are dominated by quantum mechanics which means that even slight changes in their size in their orientation get profound changes in their properties and while that's very scientifically interesting and it allows you to tune their properties by making subtle changes from a technology point of view it actually is it's a bit of a headache in the sense and technology we want to optimize for a property and then repeat that over and over again so what are some of the challenges that you face in the lab related to working with these materials and trying to incorporate them into uh into the batteries i think every step of a process in a battery is kind of something where you have to think about how would this translate to making a battery in terms of the production one thing that i think is very interesting about the field of nanoscale materials in general is that how you make the material changes the properties a lot and so if we claim that this 2d material has this property then tying that to the battery performance is something that's pretty difficult to do it takes a few steps in between so we have to think kind of creatively with how we can do that that's actually i think a very common problem we can build a device in the lab it could be a transistor can be a battery and then you ask the question okay so what's the next step how do we take it from that lab demonstration into a technology the kind of work that i'm very interested in is developing tools to make the exact type of materials that you want the tools that we use in the past for conventional fabrication just don't work with these these materials because they're all grown from the bottom up they're intrinsically small and you have to find ways to either use chemistry or some other means to get them to assemble into the structures that you want to actually either grow specifically what you want or after you grow them to pull out the ones that you want you need to be able to build that same thing over and over again with the exact same properties no one institution no one research lab no one national lab is going to solve all of these problems on their own because they are difficult problems and there is a real important payoff at the end and it's going to take all of us making our contributions to push to push these this field forward [Music] i remember reading your papers when i was a student and you know we're all trying to create these materials and finding ways to exploit their their properties what i love and i'm delighted that you're here to talk to us about is how you took inspiration from nature and sort of recognize that nature's figure out a way to both synthesize incredibly complex nanostructures with high functionality and how you sort of were inspired by that to do the research that you're that you're doing now life gave us this toolkit that is already on the nanoscale so we think that that's a great place to think about making materials on the nanoscale and manipulating materials on the nanoscale and actually and wiring them together as well this abalone shell you can see the exquisite beautiful colors and structures of it this is a nano composite material if you take this and fracture it and you look at it in a scanning electron microscope what you'll see is it's made out of these beautiful tablets and i studied that as a graduate student i looked at that and i said that is completely amazing you have an organism in the ocean that takes what's in its environment which is calcium and carbonate that's dissolved in the water and templates it into this really exquisite structure and so you think that's great calcium carbonate is great but what if we wanted to make a solar cell or a another electronic device or a a battery how would you get an organism to do that and you say okay that's a really crazy idea but is it really that crazy if this abalone you know already figured out how to do it you know 500 million years ago so we're saying okay abalones build shells can viruses build solar cells can viruses build catalysts can they build uh batteries using the same kind of idea it's really fascinating work especially now we're all familiar with with viruses and how they act and i'm not aware of any viruses that build nanostructures so i mean how did you come to that and then how do you actually you know program a virus to do your bidding we work on something called bacteriophages it's a virus with dna this particular bacteriophage called m13 bacteriophage is made up of single stranded dna and proteins it's long and thin so it's 880 nanometers in length and it's about nine nanometers in diameter and so one of the reasons i love it is it spans the nanoscale and almost the micron scale at the same time take the single strand dna obviously a model and you can cut it with molecular scissors and you can put a new piece of dna in between and so you put a small piece of dna in there that doesn't doesn't belong there and that piece of dna is going to randomly code for a protein now the next time that that virus is replicated within a bacterial host it'll be able to put a new protein sequence on the coat just a short protein sequence on the coat maybe like eight or twelve amino acids in length and just like that avalon is going to grab calcium and build calcium carbonate we're gonna have our viruses build iron phosphate for a battery electrode material or gallium arsenide or cad sulfide for a semiconductor material so you've evolved and i suppose trained these viruses to build the materials that you want them to build by exposing them to the raw materials and then you know evolving their their function we're trying to build electronics from nanomaterials the critical issue that we're facing is how do you go from those single experiments with the single material understanding its properties how do you scale that to the billions of devices that you need in a technology it is a you know a chemistry driven approach we're not going to grow them exactly where we want them but to take that one you know one step and to tie it into what you're doing it sounds like there could be an area of collaboration where instead of using sort of conventional chemistry that we can train some of these biological elements to do that to do that work work for us biology is is chemistry molecules proteins and dna work with all the same kinds of bonding and and things that the chemicals that that you're going to be looking for in these in these processes it's put together uh in a way that when a a protein or enzyme uh folds it almost always folds correctly that's kind of the beauty of it the predictable aspect of it encoded in its dna if we need to make it the same over and over again then as long as you have the right dna sequence dna is a beautiful structure on the nanoscale and there's really really cool incredible work on dna origami where dna can fold into just the right right structure and so i can see that as an interface that would be really um cool and interesting in your work and you can have the virus make the dna for the dna origami and then use dna to assemble your uh beautiful structures it's really fascinating you have all these little worker viruses building the materials for you how are you then applying these materials that you're that you're building we started thinking about how can we make an impact in cancer we do it mostly in imaging technology to look deep inside the body non-invasively with light and the way that we came about that was through solar cells and batteries we trained our viruses to pick up carbon nanotubes and hold on to them very very tightly and then we'll we'll give a virus a second gene to code for a protein to grow in the case of a battery a battery electrode material it allows it to weave together a good electrical conductor and a good ionic conductor at the same time all in the within this really really small space and the optical properties of these carbon nanotubes are in the wavelength that is interesting for imaging deep inside the body we started building a bunch of imaging tools that could image um above a thousand nanometers uh wavelength and so this is in near ir's and that's a really special window where you have some optical transparency of of tissue in the body the other gene we engineered to find ovarian cancer we developed imaging tools with harvard medical school and mit lincoln labs to find tiny ovarian tumors it's hard to see things less than a centimeter in size with ovarian cancer just based on the location in the body but with our imaging system we could find tumors that were below a millimeter in size actually looking ahead five years ten years you know where do you see your own work and maybe the field more broadly the future i'd like to see is environmentally friendly chemistry and materials synthesis and i think that we're really going that way if we think about batteries of the future solar cells of the future uh thinking about earth abundant materials and processes that are compatible with the earth and environment one of the things i love about about ammo science is it tends to break up the silos between those traditional scientific disciplines my training was in chemistry but i had a very quickly merged chemistry in physics and now i see an area where chemistry physics and biology are coming together to produce new materials and new technology into it and to advance the field forward and so being in this field you kind of have to cross-pollinate you know between these different disciplines and kind of advance the field together i agree completely we like to solve problems nanobio is the toolkit that we bring a lot it happens to be a very strong and evolving toolkit that's another thing that i love about biology is if you can come up with a solution that's not perfect at all to begin with when you're making a battery electric material or any kind of material you're making you have evolution on your side to try to make it better and better as a function of time that can be quite rapid so angela thank you so much for joining us and i look forward to seeing more work coming out of your lab in the in the future thanks for having me george it was really fun to interact and i'm very excited about our future collaboration me too absolutely i really enjoy talking to these five different people about nanotechnology nanotechnology is a field that affects all of us every day as it finds its way into a variety of applications and i hope you enjoyed it as well and see the impact that nanotechnology has on your life today and how much more of an impact it will have on all of our lives in the future

Channel: WIRED

Views: 163,444

Rating: 4.9573121 out of 5

Keywords: nanotechnology, dr. george s. tulevski, nanotech, nano, nanotechnology explained, nanotechnology explanation, nanotechnology wired, nanotechnology tulevski, nanotechnology break down, nanotechnology 5 levels, 5 levels, 5 levels nanotechnology, 5 levels wired, nanometers, nanoscale, macroscale, nanoscale objects, nanoscale properties, wired 5 levels, 5 levels interview, nanotechnology researcher, researcher, research, wired

Id: WW0IIyrq8z4

Length: 24min 0sec (1440 seconds)

Published: Thu Oct 08 2020

Reddit Comments

[u/Nachtmensch]

How fascinating. I love this and it was a great mealtime video.