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Current time:0:00Total duration:3:22

Video transcript

Imagine a material that would let you use your phone for weeks without a charge, or would let you build an elevator to SPACE!! These elevators and batteries can one day exist with a material called 'carbon nanotubes'. Carbon nanotubes are tiny. Take this human hair, for example: You would need 10,000 carbon nanotubes to make a rope as big as this hair. Despite being small, they're really strong. This cotton string holds up this Lego car fine, but if it was made from carbon nanotubes, it could hold up a real car. Carbon nanotubes are already being used around the world. Take this badminton racquet, for example. The frame incorporates carbon nanotubes, making it both lightweight and rigid, giving me a competitive edge. (Off-screen voice) Too bad you still suck. (Alex) Not only are carbon nanotubes super strong, but they can conduct heat and electricity better than the wires in your electronics. Theoretically, with carbon nanotubes, you could make a phone that goes for weeks without a charge. So why does my phone die at the end of the day and why don't I have an elevator to space?!?! Well, the truth is, carbon nanotubes are kind of difficult to make. But I can show you a way to grow them just like grass. Let's go to the clean room. Like grass, the first thing we need to do is plant the seeds. This piece of tungsten foil is going to act like our soil. I'm going to place it into the bottom of this machine, which is called a 'sputterer'. The sputterer applies a massive voltage to this piece of iron. When this happens, atoms are literally ripped from the surface of the iron and deposited onto our tungsten foil, planting the seeds for our carbon nanotubes. Now our tungsten foil is planted with tiny iron seeds, invisible to the naked eye. Let's go grow some nanotubes on them. Before we grow our carbon nanotubes, what are they actually made of? This is a model of a carbon nanotube, where each of these white balls represents a carbon atom blown up a hundred billion times larger than the actual thing. So where are we going to get all of this carbon? It's going to start out in this tank of acetylene - acetylene is a carbon-rich gas - and once I open it up, it's going to start flowing through these tubes, and continue on through this pipe, where it will eventually end up in this growth chamber. You can see that we've placed a small sample of our iron-seeded tungsten foil onto a heater, which I'll turn on now. When the iron heats up, it's going to melt into tiny droplets, like beads of water on your windshield. When the acetylene touches the hot iron droplets, the carbon is absorbed, and carbon nanotubes begin to grow like blades of grass. And this is what they look like under a high-power microscope. As you've just seen, making carbon nanotubes doesn't require some magical process. And they're already being used in common everyday objects. With more research, perhaps we'll even get our space elevators, too. Until then, I guess I'll just have to practice my game.