字幕表 動画を再生する 英語字幕をプリント Big news in the world of tiny structures—scientists may have reached the theoretical limit of how strong this particular material can get, designing the first ever super-light carbon nanostructure that's stronger than diamond. OK, I feel like here at Seeker we talk a lot about carbon nano- stuff. But what do those words actually mean? Well, carbon is a famously versatile element in the diversity of structures it can take, from graphite like in the tip of a pencil to a diamond. Both are just pure carbon, but with atoms arranged in different patterns. So carbon nanostructure literally means any arrangement of carbon atoms that results in something that can be measured on the nanometer scale, and that has novel or improved properties or functions due to its size: that includes carbon nanotubes, fullerenes, 2D graphene, carbon nanoparticles, and something called carbon nanohorns, which sounds really fun. This latest development in the nanoworld of carbon comes from a team that has designed something called carbon plate-nanolattices. Under a scanning electron microscope, they look like little cubes. The math indicated that this structure would be incredibly strong, but the difficulty of making it meant it had never been done... until now. This team's success was made possible by a 3D-printing process called two-photon polymerization direct laser writing, which is quite a mouthful. This is essentially 3D printing on the level of atoms and photons, which is definitely the coolest thing I've heard about this week. The technique focuses a laser inside a droplet of resin that is sensitive to ultraviolet light. The droplet is bombarded with two photons at a time, hence the name that 'prints' the resin into a solid. The team can use this process to create a particular arrangement of carbon struts and braces that make the structure uniquely strong and light, as well as enabling it to be a "closed-cell" structure. This has been incredibly difficult to achieve so far in the manufacturing process—usually these nanostructures have to be constructed around a cylindrical scaffold, resulting in a shape called "beam nanolattices." This seemingly small shift from a beam to a plate structure results in a lattice that's a whopping 639 percent stronger and 522 percent more rigid. This means the new design approaches the Suquet and 'Hashin-Shtrikman upper bounds,' which is a fancy way of saying this type of design proved to be just about as strong and tough as it gets. Like, we think this tiny carbon nanostructure is the strongest a material this porous can ever be—and we made it, in the lab, with a LASER! This is the first time a material that reaches those limits has ever been experimentally verified. One of the scientists on this team put it really neatly when they said that at this size, a structure like this essentially becomes a crystal, reducing its flaws and making it stronger. That's why these nanomaterials can be so freaking strong—in this case, stronger than diamond. But how can a material so small possibly be of any use on a larger scale? Well, incredibly strong nanomaterials in general promise great leaps forward in many fields, from medicine to electronics. But these carbon plate-nanolattices in particular could transform fields like aerospace engineering because of their incredible strength while still maintaining a very low density. Perfect for flying into space! But there's a long way to go before we see these used in a spacecraft. If you thought just making one cube was hard, think about scaling that up to industrialized quantities. Not an easy task. This is just the first proof-of-concept for yet another carbon nano wonder material, but with experiments like these yielding exciting results, we're well on our way to a tiny and mighty world. If you want more in carbon advancement, check out this video here, and subscribe to Seeker for more boundary-pushing materials science. And fun fact, scientists actually been making nanostructures out of carbon for the past 35-ish years since Kroto, Smalley, and Curl discovered how to do it, and won the Nobel Prize for it! If you have other carbon nanostructure news you want us to cover, leave it a comment down below, and thanks so much for watching. I'll see ya next time.