Concrete may have found it's killer app in graphene, a form of carbon from which sheets of atoms are arranged into hexagons in either a flat sheet or a tightly-rolled tube shape, that are about a million times thinner than a human hair. Unlike many manmade materials, graphene has fantastic properties. It's super strong, so much so that it can carry about twenty times more weight than any other known material (without breaking). It's strong but flexible, which makes it ideal for components of airplanes, boats, cars and spacecraft. And it conducts electricity at an amazing 300 times the rate of copper, which makes it possible to build more compact and more efficient integrated circuits than the current silicon-based ones. Because graphene sheets are so thin, they can be stacked up to form incredibly long and narrow tubes, sometimes millions of times longer than the width of a sheet, but a similar thickness. If graphene is cut at exactly the right angle it will split into two long and narrow sheets, each a few million times thinner than a sheet of paper. A ribbon of graphene rolled and cut in this way, can be coaxed into a long tube through a series of simple folds and twists. It can be flattened and cut open to make a freestanding sheet, or it can be torn open to become a square. In this form, graphene is flexible but strong, and can be rolled into a ball and twisted into a long thread. Graphene can also be used to make strong, ultrathin films that can be wrapped around a thread and used as the foundation for an incredibly durable yet amazingly lightweight, super strong and super elastic fabric. Such yarns have been around for thousands of years - Chinese silk, made from the cocoons of the silkworm, already incorporates this material. Even in the ancient world, fabric was held together by a kind of elastic tape made from a linen yarn twisted around another thread. But silk was expensive, and the filaments that made the yarn too expensive to use to make fabrics. The first modern carbon fibers, which are not actually made from graphene but from carbon nanotubes, were invented in the 1950's. It was only after an English physicist, Charles Thomas Humphreys, who was interested in creating synthetic fibers after watching spiders weave webs, went to a talk at the University of Manchester where he saw a drawing by English mathematician, William Barlow, who had worked with graphene, that he became interested in using it to make a carbon fiber. Over the next decade, he produced sheets of graphene paper, which were then ground into graphene oxide, which he converted into a carbon fiber. It took him three years of experimenting to work out the exact conditions he needed to make it, but after the breakthrough in 1963, synthetic fibers went from a promising research topic to becoming a widely-used part of clothing, industrial components and the space suit worn by Alexei Leonov during his mission to the Soviet space station, Sputnik 2. Graphene is a miracle substance. It's strong but malleable, light yet durable. The perfect material for many of the applications we've mentioned. But making it is still an expensive and difficult process that requires the use of a laboratory rather than a production line. Making it in bulk at the rate that we need it to start replacing our current materials is likely to take decades, and possibly much longer. The first graphene produced by researchers today is the second they produce, because they are made from single crystals of the most common form of graphite, graphene doesn't form naturally. The only way to get it is from wood, which is first cut into chips, then dried. If a small portion of a piece of naturally-occurring graphene is leftover it is less than a few atoms wide. It isn't until researchers start cutting and bending the crystals in various ways, that the full potential of the material becomes apparent. In a video, MIT's George Dusenbery shows just how fascinating it is. By applying voltage to a flat piece of graphene, they can generate a current, as if they were turning on a regular light bulb. This isn't due to electric current flowing through the graphene as might happen in an LED or light bulb, but rather the movement of electrons. The same thing happens when graphene is rolled into a tube, but in this case, the electrons themselves are responsible for moving through the graphene, and the energy they pass along has a lot to do with the direction that electrons move. A piece of graphene is like a thin piece of film that's about a billionth of a millimeter thick. But if it's rolled into a tube or wrapped around a thread to make a fiber, it becomes super strong and amazingly light. It's flexible, yet very strong, and so it can be coiled into a thread, or spun into a thin fiber. But what makes it especially interesting is that electrons act as a kind of switch that can be flipped on and off - either through light hitting it, or by the application of voltage in the form of a current running through it. But unlike silicon chips, graphene is flexible, and can bend in an infinite number of ways. It can't only be used for switches, it can be used in any number of different ways. What's more, the way it's switched on and off is reversible. It can pass large amounts of current, but can be switched off, and then switched on again. It doesn't break, it can be stretched, bent and torn to pieces, and then put back together as if nothing had happened. Because a current can be passed through it, it can also act as a sensor, to provide some form of feedback that's been measured and quantified. Graphene is being used in this way to make temperature sensors, where a changing current is proportional to temperature. It can also be used as a touch sensor, since electrons can't travel across a sheet of graphene. When touched, electrons will start to move, but the sensor could be used to turn off and on complex machines. The biggest benefit of the electronic switches, sensors and other innovations being made with graphene are that they could replace existing technologies. But they are also likely to be adopted by many of the technologies we already have, including the batteries used in smartphones and the components used to make them. This is because a graphene-based smartphone battery, which won't need to be replaced as often as today's batteries, could significantly extend the time before we need to buy a new one. If we can finally solve the challenges associated with making graphene, we can start to see graphene in a wide variety of ways. It can be used to make light switches, LED's, displays, to monitor temperature and detect if anything has been touched. It can even be used to make contact lenses that change the appearance of an image displayed on the lens to show your eye color to match the contact lens, and when someone touches your eye, the contact lens changes the color. It's a very far-reaching technology that in some ways has the potential to be as revolutionary as the internet. But one step at a time. A graphene-based smartphone battery would be so thin that it could be wrapped around a smartphone and replace the batteries that are currently so expensive to make, even though they are so thin they aren't even noticed when people use them. Such phones would be more durable, recharge quickly, and would last longer. But graphene isn't the only new material being found in nature that has amazing properties. Researchers at MIT have discovered another carbon-based material that has a carbon-carbon bond with a longer, stronger version of graphene, carbon nanotubes. The carbon nanotubes are hollow cylinders made of rolled-up sheets of graphene that can be joined together into endless chains of atoms. Like graphene, carbon nanotubes have useful properties, such as conductivity. But with carbon nanotubes, the carbon atoms in the nanotubes are joined in a special way called a sigma bond, a bond that's extremely strong. In fact, the strongest bond ever measured is the sigma bond, and it