READ: Graphene
If it can be produced on a large scale, graphene might be the backbone of the next revolution in electronics, building materials, medical devices, and much more. First isolated in 2004 by Professor Sir Andre Geim and Professor Sir Kostya Novoselov of the University of Manchester, graphene is one of the first two-dimensional materials discovered, composed of a sheet of carbon one atom thick. Graphene displays a suite of seemingly miraculous properties.
The semimetal is extremely light, one square meter weighing less than a milligram, but more than a hundred times stronger than steel, flexible, and highly conductive. What’s more, the material will repair itself when bombarded with loose carbon atoms. The team of researchers at the University of Manchester found that if they cut holes in a sheet of graphene, adding additional carbon atoms would cause their sample to knit back together on its own.
Graphene-enhanced concrete promises to make the mainstay building material stronger, lighter, more water-resistant, and most excitingly, could reduce the carbon-footprint of global construction by 50%.
Because graphene is so flexible, it could be used to build consumer devices like laptops and tablets that are both more durable than their existing incarnations and capable of bending and folding. Perhaps more impactfully, graphene could be used for machines and sensors to perform medical functions such as analyzing specific tissues unreachable by other means. The material could even deliver drugs to specific parts of the body without the risk of infection or the expense of many existing tools. Given that graphene consists only of carbon atoms, the second-most plentiful element in the human body, devices made from the material would be unlikely to harm patients by leaving behind toxic residue.
Electric charges fly across sheets of graphene thanks to delocalized (free) electrons in its structure. This so called ballistic transport keeps the material from heating up while conducting electricity — a very attractive property for electronics manufacture. Graphene’s conductivity opens a range of opportunities to improve on existing technology by using the new material as a substitute for silicon. Researchers speculate that replacing the silicon in photovoltaic cells with graphene could increase their efficiency from 25 percent to 60 percent, offering a critical avenue to expand production of renewable energy. Graphene even accelerates the movement of electricity along conductive polymers when those polymers are placed on a layer of graphene rather than a layer of silicon.
In addition to its strength, light weight, and flexibility, graphene is nearly impermeable to most liquids and gasses, notably excepting water. As a result, the material could be used to improve water filtration and desalination systems. A study from the Royal Society of Chemistry found that oxidized graphene could be used to remove radioactive contaminants like uranium and plutonium from water, potentially providing a new method to contend with the problems of nuclear waste and industrial runoff. Further, Lockheed Martin claims to be developing a graphene-based filter capable of removing salt from drinking water at an energy cost a hundred times smaller than that of existing desalination methods. As climate change and the resource needs of growing populations continue to put pressure on water systems, this sort of innovation could help solve problems that have long vexed policymakers and engineers.
Of course, substantial obstacles remain before graphene can be used on an industrial scale. The material is still extremely expensive to produce, and large sheets of graphene frequently develop flaws. With research on graphene, especially its regenerative properties, continuing to show progress however, engineers could very well begin to overcome these hurdles in the near future.
