Graphene: The Next Leap in Technological Advancements

ksu1Imagine a full-grown elephant balanced on the end of a pencil. Now imagine that pencil tip perpendicular to a layer of substance as thin as plastic wrap, which miraculously prevents the pencil tip from piercing through it. Sounds impossible, right? Not anymore, as James Hone of Columbia University will tell you. Not only is graphene the thinnest material known to mankind, it is also 200 times stronger than steel [1]. Racecars, airplanes, space shuttles, windmill blades, phone cases, and other strong lightweight technology will all be enhanced by graphene’s high strength to weight ratio. Scientists are also anticipating graphene to replace silicon in the next generation of high-speed electronics. Because of its amazing conductivity and flexibility, graphene may be folded, squeezed, or otherwise made more compact for even thinner, lighter, yet faster electronics [2]. In the future, these perks also may generate a foldable type of touchscreen, and perhaps an entire generation of ‘foldable’ electronics, including phones, watches, tablets, and more.

So what is graphene? It is a single atomic layer of carbon bound together in a hexagonal honeycomb arrangement. Not only does it have high stability within the layer, the thinness of the individual layers also means it exhibits an extremely high surface area to volume ratio, along with amazing conductivity [2]. Since it is made of carbon, extensive use of graphene technology will be much more ecofriendly than the heavy metals commonly implemented in most technologies [3]. The production costs would not be limited by the raw materials either; in 2011 Rice University’s Dr. Tour demonstrated that graphene could be synthesized from a diverse range of carbon sources, including Girl Scout cookies, cockroach legs, and even grass [3].

In addition, its practical applications are wide reaching. Graphene’s conductive sensitivity to surface molecules allows it to detect even a single molecule of substance. This property has allowed graphene to find applications in nanotechnology, biomedical studies, cancer research and the enhancement of superconductors [4]. By conditioning graphene to detect any molecules of cancer cells, doctors could greatly enhance diagnostic accuracy and speed, and potentially, a simple blood test with a graphene filter could detect signs of everything from harmful infections to cancer [4]. Given its sensitivity to any change in resistance to a particular molecular makeup, graphene could also be used to filter or detect specific species of microbes in an otherwise jumbled assortment of microbes, or also be used to detect faint traces of certain molecules, possibly averting chemical disasters [5]. In addition, when applied to supercapacitors, which are essentially extremely large batteries, the material’s high conductivity and large surface greatly increase their capacity—scientists have theorized that up to four times normal charge is possible [3]. This could potentially make devices like the electric car more appealing as users could have a fully charged vehicle in just minutes instead of hours.

ksu2Although something of a miracle material, the inherent difficulty of mass-producing quality graphene is due to its demand for consistent precision at every single atomic bond in the hexagonal layer. Even small deviations can severely dampen its useful properties, such as its superconductivity [6]. Also, in order to have high conductivity, graphene must be doped by intentionally adding impurities. Complicating things further, it is produced in small flakes, and thus depositing them onto large-scale areas may amplify defects that were originally found in the small flakes [6].

“Although the potential uses for graphene seem limitless, there has been no easy way to scale up from microscopic to large-scale applications without introducing defects,” says Alexander Yarin, UIC professor of mechanical and industrial engineering and co-principal investigator on the study [6].

Many methods to produce it have been implemented, for instance Andre Geim and Konstantin Novoselov won the 2010 Nobel Prize by peeling layers away from graphite using sticky tape until they had a single layer of graphene [2]. More recently, Yarin, Suman Sinha-Ray, and Sam S. Yoon were credited with developing a novel spraying technique to deposit graphene at the University of Illinois at Chicago and Korea University. Their supersonic spray system sprays very small droplets of graphene, which disperse evenly, evaporate quickly, and reduce the tendency of the graphene flakes to congeal [6]. Furthermore, to the researchers’ surprise, defects inherent in the flakes themselves disappeared, as a by-product of the spray method [6]. The researchers demonstrated that the energy of the impact stretches the graphene and restructures the arrangement of its carbon atoms into the perfect hexagons of flawless graphene [6].

“Imagine something like Silly Putty hitting a wall – it stretches out and spreads smoothly,” said Yarin. “That’s what we believe happens with these graphene flakes. They hit with enormous kinetic energy, and stretch in all directions.” [6] The new method of deposition, which allows graphene to “heal” its defects during application, is simple, inexpensive, and can be performed on any substrate with no need for post-treatment [6]. The low cost and simplicity of the supersonic spray system may make quality graphene more available for a larger range of labs to conduct research.

Considering that graphene was discovered in 2004 by “mucking about in a lab” according to Mark Miodownik of King’s College London, it’s evident we have only scratched the surface of nanotechnology [7]. As more is understood about graphene and its remarkable qualities, the wider the range of applications will be discovered in emerging technologies. The novel options offered to humankind by this thin conductor may usher in a new era of electronics, and perhaps of technology itself.

References

[1] “Columbia Engineers Prove Graphene is the Strongest Material.” The Record 21 Jun. 2008: Columbia News. Web. 04 Aug. 2014

[2] Matson, John. “Graphene Researchers Geim and Novoselov Win Nobel Prize in Physics.” Scientific American Global RSS. N.p., 5 Oct. 2010. Web. 06 Aug. 2014.

[3] Smith, Dave. “What Is Graphene? 5 Incredible Facts About The ‘Miracle Material’ You Need To Know.” International Business Times. N.p., 26 Aug. 2013. Web. 07 Aug. 2014.

[4] Yinfeng Li, Hongyan Yuan, Annette von dem Bussche, Megan Creighton, Robert H. Hurt, Agnes B. Kane, and Huajian Gao “Graphene microsheets enter cells through spontaneous membrane penetration at edge asperities and corner sites.Proceedings of the National Academy of Sciences of the United States of America. CrossMark. N.p., 13 Jun. 2013. Web. 06 Aug. 2014.

[5] “All about Graphene.” All about Graphene| Explore | Physics.org. IOP Institute of Physics, N.d. Web. 07 Aug. 2014.

[6] “Supersonic spray delivers high quality graphene layer.” Space Daily. (June 6, 2014 Friday): 544 words. LexisNexis Library. Web. 04 Aug. 2014.

[7] Alleyne, Richard. “‘Mucking About’ with Pencil Lead and Sticky Tape Wins Nobel Prize for Physics.” The Telegraph. Telegraph Media Group, N.p. 10 May 2010. Web. 07 Aug. 2014.

Image Credits:

[1] “Graphene atomic view” by James Hedberg is licensed under CC BY-NC-SA 3.0 http://www.jameshedberg.com/scienceGraphics.php?sort=graphene

[2] “Graphene Sheet” by James Hedberg is licensed under CC BY-NC-SA 3.0 http://www.jameshedberg.com/scienceGraphics.php?sort=graphene

 

Kevin Su is a senior at The Harker School in San Jose, CA. He developed his interest in graphene after spending his summer conducting research on another quantum coherent system, topological insulators, at the Francis Bitter Magnet Laboratory at MIT. Follow The Triple Helix Online on Twitter and join us on Facebook.

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