What is Graphene: A Guide to Graphene
Graphene is one of the rare materials science stories that has made its way into the popular news cycle, and stayed there. Materials are an incredibly important field, but the benefits of a better semiconductor or new kind of ceramic are usually only interesting to the average person when they produce some new consumer device. Graphene, however, is such a technological leap in and of itself, and its potential impacts are so great, that it’s becoming a household name even before it’s really hit the market. In 2010, the discovery of a way to actually create graphene warranted a Nobel Prize in Physics. So, what is graphene?
What is Graphene
Graphene is basically a slice of diamond just one atom thick. Like diamond, it’s made only of carbon atoms, but unlike diamond’s super-hard three-dimensional crystal lattice, in graphene these atoms are arranged in what’s called a two-dimensional structure. Put simply, it’s a network of carbon atoms linked together into a flexible, extremely durable sheet.
Roll the sheet up into a tube, and you’ve got a carbon nanotube, another potential super-material with world-changing abilities. Each displays an incredible combination of strength, flexibility, electrical conductivity, and miniscule physical size. Together, these virtues make the imaginations of inventors and engineers run wild.
What’s so special about Graphene
Name a tech-related industry, and it’s almost certain that a scientist somewhere has claimed graphene could revolutionize it. From all new solar panels to record-breaking skyscrapers, graphene could make sci-fi dreams a reality. Graphene-based battery electrodes could greatly increase charge capacity and lifetime, while graphene semi-conductors could create the next generation of computer processors that run at the speed of light, not electricity.
By certain measures, graphene (and new, graphene-like super materials) are the strongest materials ever discovered, on a per-weight basis, but since they only have bonds connecting the carbon atoms in two dimensions, the resulting flat sheet of carbon can be flexible in the third. This means that not only can graphene take a lot of strain, but there are many forms of manipulation that won’t even cause strain, making it even more useful. Plus, the electrons in its arrangement of carbon atoms are held so they can move with little resistance — graphene is a fantastic conducting material, and it could even lead to high-temperature superconductors.
That means that we could see enormous medical advances due to graphene, since one of the big problems with advanced medical imaging equipment today is that it requires expensive substances like liquid helium to cool its superconducting magnets. With graphene, we could see electromagnets that can achieve superconductivity at high enough temperatures that these hugely expensive substances are no longer needed — and thus, directly reduce the cost of healthcare, and the average level of access to lifesaving imaging techniques.
Scientists in laboratories have been able to make graphene do truly incredible things in very small scale, things that validate all the excitement that’s been brewing, but they have struggled to deliver on that promise in the real world. Right now there are only a few real products close to release, and they’re meant for the industrial and research markets, not regular consumers or the facilities that directly affect their lives.
Why Graphene hasn’t made it out of the lab
The problem is two-fold. One is making graphene well enough for our purposes, as bits of synthesized graphene are often “crumpled” into balls with far less usefulness than flat sheets. The other problem is making graphene cheaply enough; it’s one thing to design the world’s most amazing graphene-based solar panel, but it’s not going to change the world if it costs a million dollars per unit.
When it comes to carbon nanotubes, the issues is making them long enough, cheaply enough, and in some cases coming up with a way of weaving the strands we do create into a cable with incredible strength. The tensile strength of graphene-based carbon nanotubes is so great that if they could be made just a couple of meters long and woven together tightly enough, they could theoretically be used to create a ribbon stretching a hundred thousand kilometers above the surface of the Earth. This backbone could be used to build a so-called “space elevator,” dramatically lowering the price of getting material into orbit, and revolutionizing the human relationship with space.
The other major problem is the lack of an electronic “bandgap” for graphene. Silicon, for instance, has a moderate bandgap — it takes a moderate amount of energy input to excite an electron in silicon from the “ground” state to the “conduction” state. When we use that excited electron to do work (like generate electricity in a solar cell) we’ll get a corresponding amount of energy amount out as it drops back down to the ground stage. The electrons in graphene have no useful gap between their resting state and conductive state, which is part of what makes graphene such a great conductor, but it also means that graphene is hard to use in certain advanced applications that need a bandgap to work.
Research is well on the way to solving both problems. Manufacturing graphene is getting cheaper and higher-quality by the day, and it turns out that graphene can inspire a number of related, two-dimensional super-materials that shore up many of its core weaknesses. It’s possible that graphene development will progress in a small number of huge leaps, where a numerous applications are researched in the lab, but stay there as they wait for manufacturing breakthroughs. When those breakthroughs come, making the previous research viable for sale, the pace of advancement could spike dramatically.
What’s next for Graphene
Graphene is a substance that could make the dreams of engineers and science fictions writers come to life — but it also has the potential to allow forms of innovation few have considered before. Carbon nanotubes are small enough and they could be used to reach inside individual cells and affect sub-compartments. Graphene-based hull materials could be the basis for new modes of transportation that require low density and high strength; more affordable trans-Atlantic flights would almost certainly be in the cards.
The possibilities are incredible to think about, so much so that they make otherwise dry discoveries in materials synthesis into dramatic public events. When graphene does get its second big breakthrough, the one that lets it move from the lab to the wider world, it will be a monumental day, followed by many more such days quickly after.