Lesson video

Hello and welcome to today's lesson on the discovery and uses of carbon nanostructures from the unit, Chemistry of Carbon.

Hopefully by this point you have covered a little bit on the different allotropes of carbon, including things like diamond graphite and graphene, perhaps even fullerenes and carbon nanotubes.

Today in this lesson we're gonna go through the discovery process of these different carbon nanostructures and we're gonna talk about some of their properties and their uses.

So the outcome for today's lesson, what you should be able to achieve by the end of this lesson is you should be able to describe the discovery process, the scientific discovery process, and relate the uses of nanostructures to their properties, structure and bonding.

There are three keywords that we're gonna focus on throughout this lesson.

They're graphene, fullerene and nanotube, and the definitions are on the next slide, but we can go through them as we get to them in the lesson.

So this lesson is split into two parts, the discovery process and the properties and uses of the various different carbon nanostructures.

And we're gonna start with the discovery process.

So a lot of different scientific discoveries are actually accidental.

A lot of scientists work very hard on the research that they are conducting to reveal the discoveries that they're aiming for, but by accident sometimes new things are discovered and we're gonna look at a couple of examples.

The first one is this colour on the right hand side, this lovely mauve colour or this lovely purple colour, it's called mauveine.

It's a purple synthetic dye and it was discovered by William Perkin who was actually attempting to synthesise a cure for Malaria.

Percy Spencer, was working on some research to do with radar and in the process ended up realising that certain different frequencies warmed things up or effectively cooked them and invented, in the process, the microwave oven.

And Stephanie Kwolek was working on fibres for tyres and ended up doing some of the major research that and discovery process that led to the formation of what is now known as Kevlar.

So why is that relevant? Well, because a lot of the various different discoveries we're gonna look at today in the context of carbon nanotubes were also discovered accidentally, or at least that was not the intention of the researchers, that or at least that was not the intention of the researchers that were doing the work.

So graphene, fullerenes, and nanotubes share carbon as their fundamental building block.

Pure structures of these are only made of carbon atoms, however the discoveries unfolded in quite different ways.

So graphene was hypothesised to exist long before fullerenes.

It was thought fullerenes were potentially available to us, but perhaps maybe they weren't very stable.

And however the fullerenes were discovered and isolated quite a lot earlier than the graphene was.

Despite how easy, as we'll see a little bit later, the discovery process was for graphene.

Incidentally though, the discovery process for the fullerenes was not intentional.

The research team behind it were actually doing research into giant red stars.

They were doing some astrophysics or astro chemistry research and unintentionally discovered C60, which you may know has the name of Buckminsterfullerene.

It's named after Buckminster Fuller, who was famous architect for the style of building, which were kind of domes or spheres that had these hexagonal pentagonal rings like are found in the structure of Buckminsterfullerene C60.

This eventually led to the team of Kroto Curl and Smalley winning a Nobel prize in chemistry in 1996.

So they were hypothesised in the 1970s.

They were discovered in the 1980s and there was an award given to scientists in 1996.

Not every scientist will end up winning an award for their research then only one person or one team of people can win the Nobel prize every time that it is awarded.

And which is why sometimes it can take a while for some teams to be awarded a Nobel prize for their work because there are other discoveries that are in the runnings, so to speak, to win a Nobel prize.

So a quick recap on what we've done so far.

Multiple choice question for you.

The history of carbon allotrope research demonstrates the collaboration between different scientific fields is crucial to some discoveries.

Theoretical work often precedes experimental breakthroughs.

Accidental discoveries can revolutionise fields of science and the path of scientific progress is always predictable.

I'd like you to pause the video now as you have to think about those statements.

Which ones do you think are true? There might be more than one and we'll go through this in a short second.

Okay, so which of these are true statements? Well, collaboration between scientific fields is crucial to some discoveries.

So as we saw the discovery so far of C60, a type of fullerene was discovered by a research team looking at giant red stars.

So they weren't specifically in the discipline of working on carbon chemistry, or at least to discover carbon allotropes.

Theoretical work often precedes experimental breakthrough.

So it was about 10 years before carbon fullerenes were actually isolated.

They were made in a lab or at least discovered and seen in a lab, but there was work being done 10 years prior.

Theoretical work on their actual existence.

We saw again that C60 is an accidental discovery and we looked at a couple of other non-carbon examples of accidental discoveries and they really can revolutionise fields of science.

The only one here that isn't true is that the path of scientific progress is always predictable 'cause it's not.

We don't know how long research will take.

We don't know how long it will take once we've started that research to discover something and we don't necessarily know what the outcome of that research will be.

True or false? The molecule C60 was given the name Buckminsterfullerene because it was initially designed for construction purposes.

True or false? Well the answer to that question is false.

And I'd like you to have a read through these two justifications and pick the one that makes kind of the most sense.

Which one is the correct description about why this statement is false? Pause the video now as you have a think about that and press play when you are ready to continue.

Well the answer is A, scientists named C60 after Buckminster Fuller due to the structural similarity to his geodesic domes.

What a great word.

Buckminster Fuller was an architect.

He did not collaborate on the project for C60.

It wasn't a scientist.

So on the right hand side here we can see some of the first images of carbon nanotubes.

These were first seen in the early 1950s.

However they were mostly ignored.

Scientists at the time didn't really know what they were or weren't interested in what they were, but we now recognise them as the first observations of carbon nanotubes.

It wouldn't be until the 1990s though that a scientist named IIjima would clearly identify and characterise the unique structure of carbon nanotubes.

This prompted more research into the carbon structures, kickstarting effectively a new field of organic chemistry.

True or false then? Effective scientific communication is primarily important for other scientists and has little impact on the general public.

True or false? The answer is false.

I'd like you to read through the next two justifications.

Pause the video while you do so and then display when you're ready to find out the answer.

Well the answer is A, scientific communication to the public influences funding, policy changes, and understanding of important issues like climate change.

Scientists do need clear communication to collaborate and build upon each other's work.

But the main theme here is kind of we're saying that the general public do need to be aware of scientific research and they need to have effective communication to understand why it's important.

So we're going even further back in time now we're gonna go back to the 1940s.

This was when the first idea that graphite could be split into individual layers was proposed.

I don't think that the idea of the name of graphene was suggested at this time, but we had suggested that the graphene structure might have existed.

This is nearly 30 years before we're talking about carbon fullerenes.

And even earlier, about 10 years before carbon nanotubes were first kind of discovered, but nearly 50 years before they were first really talked about in the mainstream.

However, it took until the early 2000s and nearly 60 plus years to actually discover graphene.

And all it took was a little bit of sticky tape stuck on a piece of graphite and ripped off very carefully.

And they found that they had a very, very thin layer of graphite.

That one atom thick layer of graphite is now known as graphene.

However, again, they wouldn't be awarded for their research until the 2010.

So it took even longer, not as long as it took for carbon nanotubes to be awarded a Nobel prize, but again, took a little bit of time for them to be recognised for their achievement.

So which of the following statements about carbon allotrope discoveries are true? We've got four statements here.

We've got graphene was isolated before carbon nanotubes.

We've got the scientists discovering fullerenes were aiming to study carbon formations in stars.

Early scientific papers theorised about graphene and fullerenes decades before their isolation.

And each scientist involved in isolating a carbon allotrope went on to win a Nobel prize.

Have a pause, have a read through and when you think you know the answers, press play and we'll continue.

So the answers are B and C.

Graphene was isolated last and not every scientist went on to win a Nobel prize.

Nobel prizes only went to those who studied C60, carbon fullerenes and to graphenes.

Those that worked on the carbon nanotubes weren't awarded at a Nobel prize.

So we've got four students here discussing the discovery of carbon allotropes.

I'd like you to have a read through the statements, decide who you think is correct, partially correct and who is just incorrect.

And why? Why do you think that? Perhaps maybe even suggesting alternatives to what they've written to make their statements correct if you don't think that they are fully correct.

This is a slightly longer task.

I'm gonna pause the video now or you need to pause the video now.

And when you're ready for the answers, press play.

So Izzy has said, "Fullerenes were named after an architect because they were originally going to be used in buildings." That's a misunderstanding about the fullerene naming.

They aren't names that way because they were going to be used in buildings, but they were named after an architect who had buildings that had a similar kind of shape to the structure.

Jacob says that, "Carbon nanotubes are basically a sheet of graphene wrapped into a cylinder shape." This is correct, carbon nanotubes are effectively just one atom thick layer of graphene or graphite, but they are wrapped into a cylinder.

Laura says, "They gave Nobel prizes to all of the different scientists who discovered all of those carbon things." Not quite true.

Only the discovery of graphene and fullerenes as we talked about were awarded Nobel prizes for physics and chemistry, respectively.

So graphene for physics and for fullerenes for chemistry.

And Lucas says, "I think graphene was discovered first since it's just one layer of graphite that makes sense." However, this is not correct but understandable because it kind of feels like it's the most basic of all the structures, but it was actually discovered last.

In order of discovery goes technically fullerenes, then nanotubes, then graphene.

But nanotubes were observed before they were kind of officially discovered.

So I've given you kind of a breakdown there of those answers.

So again, if you wanna pause and have a read through those, feel free to and then press play when you are ready to continue.

So now we're going to talk about some of the properties and uses of the carbon nano structures.

You might have covered these a little bit before, in which case this should be a good piece of recap for you, but if you haven't then you will find some of this knowledge very useful to understanding how carbon allotropes are related to the world around us.

So each allotrope of carbon has its own set of properties and uses.

I think that should hopefully be fairly apparent.

Otherwise we wouldn't need lots of different types of structure.

And when they were first proposed each of these different structures, scientists suggested some different uses.

But those uses for those different structures are not necessarily the uses that we use them now.

Kind of this hypothesis, this idea of discovery and then what the discovery could be used for, it's all part of the scientific discovery process.

What we actually end up using our discoveries for can be quite different to what we initially wanted them to be used for or they could be useful and that's for lots of different reasons.

It might be cost, so it might be very expensive to use 'em for those reasons.

It might be that what they were suggested for wasn't actually a very viable use, but it was thought that it might be, or there could be lots of other different challenges involved in getting them to be widespread.

So here are three of the main reasons that kind of some of these structures aren't as popular or as used as they were thought to be at this stage.

The first one is that graphenes large scale production is very expensive, it's very costly, nanotubes can be very difficult to get them to align uniformly.

So that means in the same way every time and there are potential toxicity concerns over fullerenes.

So we don't know whether they are fully safe to use in the ways that we intended for them to be used.

So we're gonna look at each different structure in term.

We're gonna talk about their structure, we're gonna talk about their properties and then we're gonna talk about some potential uses.

So carbon fullerenes, those kind of spherical structures have some very useful properties.

So they're cage-like molecules, that's how they're described.

They often described to look very similar to footballs, especially C60.

They have a very reactive surface.

So those carbon atoms are very reactive and they can react with other atoms or molecules.

They are very soluble in organic liquids.

So that's liquids that are mostly made of carbon structures.

So they're not soluble in water and they're very good at electronic sceptres.

So they have the delocalized electron system like graphite does.

They aren't able to conduct electricity because they don't pass those electrons between the different molecules.

But they can accept electrons from other molecules and form anions.

So negatively charged ions.

That can be very useful for electronics and chemical processes but it doesn't allow them to conduct electricity.

So when they were first proposed, there were quite a few different suggestions on how they could be used.

The first one being a drug delivery system.

Idea being that we could store drugs inside of the cage-like structure, we could inject them into people and they would do a slow release rather than kind of having to have regular injections of various different types of medication or taking lots of different tablets.

They were suggested that they could be used as catalyst because they've got a very good surface area to volume ratio.

We could potentially use them in solar cells.

So solar powering because of their ability to accept electrons.

Again in electronics or perhaps maybe as antioxidants because they're very reactive, they might be able to react with oxygen to remove what's known as oxygen radicals from our bodies.

However, current uses are not quite the same.

So we use 'em as lubricants.

As you may already know because of their slippery nature, they're able to slide over each other very easily.

They're medical imaging agents so we use them to help us take photographs of or kind of images, maybe not specifically photographs of various parts of our bodies which might be difficult without their usage.

We use them as reinforcement in materials.

So we might use them in a composite material as the reinforcement.

And we do use them in cosmetics but has maybe not to the same degree that was initially proposed.

There's also some current research into electronics catalysis and drug delivery as we've already discussed.

So we're getting close to the point where we might use them in those areas but also in quantum information systems. Now quantum computing and quantum information systems are very, very current right now.

They're proposed that in the next five to 10 years we might have what's known as this quantum computing.

It's not really chemistry, it's more physics and computing.

But if you're interested it's definitely something worth looking into.

So true or false? Fullerenes are primarily used in electronics today due to their excellent conductivity.

True or false? Well the answer is false.

I'd like you to read through these two statements and have a think about which one is correct and press play when you're ready to hear the answer.

Well the answer is B, fullerenes applications mostly focused on areas like lubrication, medical imaging and material reinforcement.

We don't really use them in electronics for their conductivity.

They are used quite widely in electronics though not for their ability to conduct electricity though.

Carbon nanotubes have similar properties to fullerenes as we know they're made of very similar structures.

However, rather than being spherical cages, they're more like tiny hollow cylinders made up of a rolled up sheet of carbon atoms. They're incredibly strong, they've got very high tensile strength, many times stronger than steel for their comparative weight.

They are excellent conductors of electricity 'cause they are very long molecules.

They do allow the conductor because they are very long molecules that does allow them to conduct electricity.

And because of that, that also means they're very good heat conductors as well.

So they're very good at managing heat transfer.

Individual nanotubes are very flexible but they do tend to clump together and that does reduce their flexibility.

Now all of those properties lend it to some potential uses such as reinforcing materials due to their high tensile strength 'cause they can conduct electricity, they might be very good in electronics.

There was a suggestion that they might be able to store hydrogen, which is a very flammable explosive gas.

Potentially, for long-term use of hydrogen in hydrogen fuel cells.

They were thought that they might be able to be used as biomedical sensors, so because of their electrical conductivity.

And one of my favourite suggestions is this idea of a space elevator, this elevator that will take resources and people up into space at a very low budget rather than having to use rockets.

So these were all suggested when the discovery was first made.

However, that's not quite the scenario that we have today.

These are the different uses of carbon nanotubes at the moment.

So they are composites, so that's mixtures of other materials together to make a different material that has more enhanced properties.

So they're used in things like aerospace and sporting equipment.

We are using them in electronics as transistors and in wiring.

They are used for energy storage, so in batteries and super capacitors.

And they do have biomedical applications.

So we are using them for drug delivery and for tissue scaffolding, so that's bio tissue.

So that's your cells rather than tissues as in what you blow your nose with.

There is also some promising research into their use infiltration systems as well as advanced textiles.

And we are still working on this idea of a space elevator.

So which of the following are current or potential uses of current nanotubes? Thinking to what the information was that we've just been given on their current uses or potential uses.

Have a read through, once you think you have an answer, press play.

So press pause whilst you're thinking and we'll go through the answers in a second.

So the answer is in fact all of them, let's go through why.

So we said that they can be used in composites to reinforce materials, especially in sporting goods.

So reinforcing tennis rackets.

We also said that they could be used in aerospace so they're actually used to build lighter and more efficient spacecraft.

We've said that they've been used in biomedical situations for drug delivery and we've also said that they've been used for tissue scaffolding.

So all of those are uses of carbon nanotubes.

We're gonna now look at graphene.

So graphene is known to have some very useful properties as well.

We know it's a single layer of carbon atoms arranged in a hexagonal ring pattern, it's just one atom thick.

The carbon atoms like in fullerenes are very reactive so we can react them with other substances.

They're excellent conductors of electricity.

So they have delocalized electrons again that can move through their structure.

They are nearly transparent, which means that we can use them in scenarios that might allow us to conduct electricity but also see through the structure at the same time and they're incredibly flexible.

So all of these are really useful properties, specifically in things like electronics.

So they weren't originally kind of just thought about from an electronic standpoint.

We thought that we might be able to use them for variety of different things like carbon nanotubes and fullerenes.

Things like ultra strong lightweight materials, high speed transistors, water filtration systems and energy storage.

But the main one that most people thought that they could be used for was for touchscreens and flexible displays.

We do use them quite a bit for that in kind of modern mobile phone devices.

You might have seen the phones that you can cover them around your arm.

You might have seen those new kind of flip phones that are kind of curved.

There's a lot more in production currently, but we do use 'em for quite a lot of other reasons and we use 'em for sensors, composites again in aircraft and construction and again in biomedical applications.

And again a bit like carbon fullerenes and nanotubes.

There are quite a lot of extensive other areas of research ongoing at the moment for potential uses as well.

True or false then? A single layer of graphene is practically invisible to the naked eye.

True or false? The answer is true.

I'd like you to have a think about which of these two answers justifies that? Pause the video whilst you do so and press play when you are ready to continue.

So there are three main reasons why discovery may not end up being kind of used for the suggested uses at that time of discovery.

And the first one is production hurdles.

Sometimes it can be quite difficult to scale up from a lab environment to a large scale manufacturing process.

Most of the time it can be due to a high production cost but it can also be due to keeping the material pure.

So it might become contaminated through the process.

Competition, so whilst you are developing something, another team might be developing the same thing and they may have access to newer materials or higher quality research that you weren't aware about, and end up producing something cheaper or faster than you are possibly able to.

But also it just takes time.

Science is not something that you can just switch on and there's an answer.

It takes a lot of steps and a lot of different processes to get to a new discovery and breakthroughs are needed.

Sometimes we can get very stuck in certain ways and then suddenly you will see on the market brand new devices that seem to have huge leaps in technology and that'll be due to breakthroughs.

Okay, so here are some statements.

Some of them are true, some of them are not.

You need to decide which ones are.

The development of carbon allotropes highlights that what? So pause the video now whilst you're having a think about these statements and then when you are ready to hear the answers, press play.

So there's only one correct answer here and it's C.

Advances in technology can unlock new uses for a material.

Initial theories of material properties are always shown to be incorrect, it's just not true.

That the most useful applications of a discovery are always foreseen immediately.

Again, not true.

It normally takes a while and commercial success of scientific discoveries is guaranteed, not true.

There are a lot of scientific discoveries that happen that you don't hear about or sometimes you do hear about and then just nothing, no news on them because we just can't find a commercially viable use for that discovery.

It might be in another 10, 20 years time that we can, but a lot of discoveries don't go published or at least into the main public.

True or false? It's normal for scientific discoveries to take many years to become widely used technologies.

That is a true statement.

And I want you to read through these two statements below these two justifications and pick the one that is the best as to explain why that is true.

Well the answer is A, the process from discovery to application often involves research, breakthroughs and technology development.

Scientific discoveries don't often lead to commercial success within a couple of years and that wouldn't be a factor that decides whether it was a successful product.

Okay, we've got some tasks now to have a look at.

This first one is a piece of homework set to Jun.

Jun has worked on his homework and he was asked to answer the question, explain why the development of fullerenes, nanotubes and graphene has taken a long time despite early excitement.

His answer says these carbon things are all too small to really be useful.

It's hard to work with them.

So that's why not many products use them.

I'd like you to provide a better answer to this question and I'd like you to include information about production limits, competition, and the general nature of scientific development.

So pause the video now, have a go at that and when you're ready to have a look at some potential answers, press play.

So I've got a few answers here.

Focusing on those three main areas that were discussed and I'm gonna have a read through them, see if you've got any of those and you might have some more.

This is an an exhaustive list.

So whilst there was initial excitement about the potential of fullerenes, nanotubes, and graphene, several factors explain why the development and widespread use have been slower than expected.

Producing these materials at scale with consistently high purity is currently very expensive.

Other newly developed materials may offer similar performance at lower costs, creating competition and the scientific process is rarely a straight line.

Discoveries, technological advancements, and breakthroughs are often needed to turn initial potential into practical applications.

My second task to you is to take what we know about graphene and design a new product incorporating graphene that takes advantage of at least two properties.

So I'd like you to draw a design, I'd like you to label it and I'd like you to briefly justify how the properties of graphene, such as being strong for its size, being incredibly thin, flexible, conducts electricity are used in your design.

So pause now as you have a go at this and press play when you'd like to see my suggested answer to this question.

So my suggested design is a wearable phone so it wraps around your wrist.

We talked a bit about this earlier in this lesson.

However, there are quite a few different types of design you could have come up with, such as an ultra thin, strong protective layer for a phone screen, a bit like mine, a flexible yet strong kind of components within a phone.

So wearable technology or perhaps maybe lightweight, durable material for things like vehicles.

So I proposed a flexible rollup touchscreen display constructed with graphene for the screen.

Graphene strength and flexibility would allow the screen to retain its functionality even when repeatedly rolled and unrolled so it doesn't break or crack.

It's extremely thin, it would enable a remarkably compact device, easy to wear or fit into small spaces compared to a standard conventional smartphone.

So well done on those if you had a go and had something very similar.

I think we've had a a really good lesson.

I think this is a very interesting topic.

Just to summarise what we've gone through then.

Scientists discovered an isolated fullerenes accidentally, which led to exciting new possibilities in chemistry.

Research into the allotropes of carbon is an important part of chemistry's history and has earned multiple Nobel prizes.

Graphene is so thin that it is nearly transparent, allowing most of the light to pass straight through.

Fullerenes, nanotubes, and graphene have a wide range of real world uses in fields like electronics and medicine.

And scientific discoveries have the power to change the world, even if their significance takes time to be fully understood.

I hope you enjoyed this lesson.

I've enjoyed going through this lesson with you.

And I look forward to seeing you in the future lessons.

Thank you.