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In simple terms, graphene, is a thin layer of pure carbon; it is a single, tightly packed layer of carbon atoms that are bonded together in a hexagonal honeycomb lattice. In more complex terms, it is an allotrope of carbon in the structure of a plane of sp2 bonded atoms with a molecule bond length of 0.142 nanometres. Layers of graphene stacked on top of each other form graphite, with an interplanar spacing of 0.335 nanometres.
It is the thinnest compound known to man at one atom thick, the lightest material known (with 1 square meter coming in at around 0.77 milligrams), the strongest compound discovered (between 100-300 times stronger than steel and with a tensile stiffness of 150,000,000 psi), the best conductor of heat at room temperature (at (4.84±0.44) × 10^3 to (5.30±0.48) × 10^3 W·m−1·K−1) and also the best conductor of electricity known (studies have shown electron mobility at values of more than 15,000 cm2·V−1·s−1). Other notable properties of graphene are its unique levels of light absorption at πα ≈ 2.3% of white light, and its potential suitability for use in spin transport.
Bearing this in mind, you might be surprised to know that carbon is the second most abundant mass within the human body and the fourth most abundant element in the universe (by mass), after hydrogen, helium and oxygen. This makes carbon the chemical basis for all known life on earth, so therefore graphene could well be an ecologically friendly, sustainable solution for an almost limitless number of applications. Since the discovery (or more accurately, the mechanical obtainment) of graphene, advancements within different scientific disciplines have exploded, with huge gains being made particularly in electronics and biotechnology already.
The problem that prevented graphene from initially being available for developmental research in commercial uses was that the creation of high quality graphene was a very expensive and complex process (of chemical vapour disposition) that involved the use of toxic chemicals to grow graphene as a monolayer by exposing Platinum, Nickel or Titanium Carbide to ethylene or benzene at high temperatures. Also, it was previously impossible to grow graphene layers on a large scale using crystalline epitaxy on anything other than a metallic substrate. This severely limited its use in electronics as it was difficult, at that time, to separate graphene layers from its metallic substrate without damaging the graphene.
However, studies in 2012 found that by analysing graphene’s interfacial adhesive energy, it is possible to effectually separate graphene from the metallic board on which it is grown, whilst also being able to reuse the board for future applications theoretically an infinite number of times, therefore reducing the toxic waste previously created by this process. Furthermore, the quality of the graphene that was separated by using this method was sufficiently high enough to create molecular electronic devices successfully.
While this research is very highly regarded, the quality of the graphene produced will still be the limiting factor in technological applications. Once graphene can be produced on very thin pieces of metal or other arbitrary surfaces (of tens of nanometres thick) using chemical vapour disposition at low temperatures and then separated in a way that can control such impurities as ripples, doping levels and domain size whilst also controlling the number and relative crystallographic orientation of the graphene layers, then we will start to see graphene become more widely utilized as production techniques become more simplified and cost-effective.
Being able to create supercapacitors out of graphene will possibly be the largest step in electronic engineering in a very long time. While the development of electronic components has been progressing at a very high rate over the last 20 years, power storage solutions such as batteries and capacitors have been the primary limiting factor due to size, power capacity and efficiency (most types of batteries are very inefficient, and capacitors are even less so). For example, with the development of currently available lithium-ion batteries, it is difficult to create a balance between energy density and power density; in this situation, it is essentially about compromising one for the other.
In initial tests carried out, laser-scribed graphene (LSG) supercapacitors (with graphene being the most electronically conductive material known, at 1738 siemens per meter (compared to 100 SI/m for activated carbon)), were shown to offer power density comparable to that of high-power lithium-ion batteries that are in use today. Not only that, but also LSG supercapacitors are highly flexible, light, quick to charge, thin and as previously mentioned, comparably very inexpensive to produce.

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