Atom thick graphene: the new super material

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Just as bronze, iron, and steel have driven new technological advances over the course of history, shaping societal developments and ultimately determining geopolitical superpowers we recognise today, a new material- graphene- has the potential to alter our future today. Considered a ‘wonder material’ by scientists currently grappling over how to better understand it, graphene’s seemingly infinite list of remarkable characteristics could have drastic implications for the future of engineering and technology.

Graphene is a single, thin layer of graphite, which is an allotrope of carbon. The carbon atoms in graphene are structured in a hexagonal arrangement resembling a honeycomb. Being one atom thick, graphene has already made history in being the first two-dimensional material ever discovered. Moreover, with a tensile strength of 130 gigapascals, it is over 100 times stronger than steel and one of the strongest materials known thus far. Not only does graphene have an unbelievable strength considering how thin it is, but graphene is also flexible, transparent, highly conductive, and impermeable to most gases and liquids. Despite graphite being used since the Neolithic era, until recently graphene was a myth since scientists doubted if we would ever be able to isolate graphite down to a single, atom-thin sheet. Funnily enough the tool ultimately changing the world in this case was merely sellotape. By peeling layer after layer of graphite from a large block, scientists Andre Geim and Konstantin Novoselov were eventually able to generate the thinnest possible sample: graphene. Since then, the list of potential uses has grown exponentially year after year.

Currently, our phones, laptops and other electronic devices rely on silicon as a key component. However, silicon transistors will soon be reaching the limit at which they can be effective, ultimately rendering these technologies slower and counterproductive. With graphene as their conductive element, it may be possible to manufacture ultra-thin and flexible touch screens that would be essentially unshatterable due to graphene’s strength. Smartphones would be as thin as a piece of paper, flexible, and light since touch screens can be printed on thin plastic rather than glass. Furthermore, graphene can be tuned to behave as both an insulator and a superconductor. This allows for both the investigation of unconventional superconductivity in science as well as opening many possibilities for new quantum devices.

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For example, graphene can be utilised for improving current protonconducting membranes, which are essential segments of fuel-cell technology. This combined with the fact that graphene’s impermeability to even the smallest of atoms still allows it to be used to sieve hydrogen atoms stripped of their electrons, indicates graphene could be used to construct mobile electric generators powered by hydrogen extracted from the air. In the future, vehicles and electronics could be fueled by small amounts of hydrogen in the air around us.

From a less engineering-related standpoint, graphene could be invaluable for alleviating water shortages worldwide. Another exception to graphene’s impermeability is water as it can evaporate through graphene. This renders graphene an excellent tool for filtration and it could be incredibly helpful in purifying water of toxins. Some of the most notorious environmental hazards, including nuclear waste and chemical runoff, could be cleansed from water thanks to graphene. Indeed, a study at the Royal Society of Chemistry proved oxidized graphene could even filter out radioactive materials such as uranium and plutonium present in water, leaving the liquid free of contaminants. After nuclear incidents, like that of Chernobyl, which polluted food and water supplies all over Europe, a discovery like this can alleviate the growing global strain due to a dwindling freshwater supply. As overpopulation continues to be the most pressing environmental concern, maintaining clean water supplies will become ever-increasingly crucial. Over a billion people suffer from water scarcity, a figure that is constantly rising, and graphene filters could hold the billion dollar answer for improving water purification, and increasing the amount of safe freshwater available. Moreover, engineers have recently developed a graphene filter called ‘Perforene’, which could reduce the amount of energy required for reverse osmosis in desalination plants to filter out salt of seawater.

The potential uses of graphene are infinite. From hair dye to bulletproof vests and rust prevention measures. One interesting potential use of graphene, however, is for mosquito defense. Although this is surprising, researchers at Brown University have devised a logical explanation: a graphene film on the skin physically blocks mosquitoes from biting, thanks to graphene’s impermeability, and also mitigates them from coming into contact with us in the first place. A possible explanation is that it prevents mosquitoes from being able to smell the prey, so perhaps there is some sort of chemical barrier within graphene.

It is obvious by now that graphene has very many strengths and uses. Since its discovery 17 years ago, research has consistently identified new uses and ways to revolutionise not only science and engineering, but also society and health as a whole and we may be able to split other potentially

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semiconductor materials into atomthick layers. Although graphene is still extremely costly to produce in mass quantities, which consequently limits research possibilities, the future of graphene and its impact on humanity is bright. The existence of silicon was revealed almost a century before silicon semiconductors paved the way for computers. Only time will tell whether graphene will be the resource driving the next era of human history. Just like the stone and bronze ages, we may even live in a graphene age one day.

By Tabitha Iliffe

References and further reading: https://bits.blogs.nytimes.com/ 2012/10/12/graphene-could-usherflexible-ultra-slim-gadgets/?_r=0

https://www.treehugger.com/waysgraphene-could-change-theworld-4863867

https://www.explainthatstuff.com/ graphene.html

https://www.theguardian.com/science/ 2013/nov/26/graphene-moleculepotential-wonder-material

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Marie Maynard Daly

Of the most influential women in Chemistry, Marie Maynard Daly stands out significantly as being the first African American woman to obtain a PhD in the United States. She fought battles of both gender and racial bias whilst participating in crucial research involving the effects of biological molecules on the organisms. Not only is she an inspiration in the scientific field, she is also an inspiration to women and African Americans.

She was born on April 16, 1921, and raised in Queens, New York, in a modest household. Her father worked as a postman, after being forced to drop out of his degree in chemistry, at Cornell University, because he was unable to afford the tuition. Her mother had a passion for literature, which strongly influenced Marie as a child. After graduating from her high school, Marie pursued her undergraduate degree at Queens College (also in New York) before moving onto her graduate degree, in chemistry, at New York University. She exceeded expectations at both schools, graduating ‘magna cum laude’ from NYU- essentially an academic award of distinction, awarded to very few students.

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“Courage to be is the key to revelatory power of the feminist

revolution.”- Dr Marie Maynard Daly

In 1943, Marie was admitted into the PhD program in chemistry at Columbia University, New York. This was a huge achievement for Marie, as a woman, and especially as a woman of colour. As well as her immense hard work and diligence to earn this acceptance, she was also aided by the timing of her application. Due to many men leaving to fight in World War 2, there was a shortage of scientists working across the country. As a result, many schools were encouraging and admitting more women to enter the field and obtain PhDs. Led by the successful American chemist- Mary L Caldwell- Marie studied, in depth, the role of chemicals produced by the body in the process of digestion. After three years, she was awarded her doctoral degree in chemistry, officially securing her title as the first African American woman to receive a PhD in history.

Following her monumental achievement, Daly went on to be a professor of biochemistry at Columbia University. As well as this, she did a lot of research with other scientists on what heart attacks are caused by and, more importantly, the link between the fat cholesterol and how it blocks

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arteries (ultimately leading to heart attack.) Moreover, Daly was influential in developing multiple programmes to encourage minority students to enroll and attend science-related courses at universities across the country. Eventually, she retired in 1986 and died in 2003 but her achievements as a scientist and woman of colour still remain an inspiration to young scientists all over the world.

By Aya Kodmani

References and further reading: https://www.biography.com/scientist/ marie-m-daly

https://www.sciencehistory.org/ historical-profile/marie-maynard-daly

https:// blackhistory.news.columbia.edu/ people/marie-maynard-daly

https://www.medicalnewstoday.com/ articles/dr-marie-maynard-daly-thefirst-black-woman-with-a-phd-inchemistry

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Editors’ Picks

Our favourite books:

Non-fiction

The Poisoner’s Handbook - Deborah Blum The Disappearing Spoon - Sam Kean Herding Hemingway’s Cats - Kat Arney Why chemical reactions happen - James Keeler Mathemagics: How to look like a genius without really trying - Arthur T. Benjamin and Michael Shermer

Fiction

This Mortal Coil Series - Emily Suvada (seventeen-year-old Cat must use her gene-hacking skills to decode her late father’s message concealing a vaccine to a horrifying plague.)

Brave New World - Aldous Huxley (set in a futuristic World State, inhabited by genetically modified citizens and an intelligence-based social hierarchy.)

Do Androids Dream of Electric Sheep? - Philip K Dick (set in a post-apocalyptic San Francisco, where Earth's life has been greatly damaged by a nuclear global war, leaving most animal species endangered or extinct.)

Podcasts:

Chemistry in its Element- a wonderful tour of the periodic table and the many chemical compounds found worldwide in a series of short episodes

Stereo Chemistry- this is amazing for learning about chemistry’s frontiers and exciting research happening around us

Chemistry in Everyday Life- explains chemical phenomena and how they manifest all around us

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Music:

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Teachers’ Picks

Miss Mills- Antimony, Gold, and Jupiter’s Wolf: How the elements were named (By Peter Wothers) Dr Hollis- Atkins’ Molecules (By Peter Atkins)

Miss McLaren- The Poisoner’s Handbook: Murder and the Birth of Forensic Medicine in Jazz Age New York (By Deborah Blum) Mr Upton- Molecules of Murder (By John Emsley)

Ms Whitby- Dr Harnett- “Chemistryhttps://myheplus.com/subject/chemistry Support for sixth form studies” resources on the library website

Dr Badger- Chemistry: A Volatile History Miss Smart- (BBC Four) https://player.fm/podcasts/ Chemistry-Education (Collection of podcasts)

Miss Lloyd- Crash Course Chemistry Ms Andrade- Why Chemical on youtube Reactions Happen (By James Keeler and Peter Wothers)

Mrs Swann- Shocking History of Phosphorus: A Biography of the Devil’s Element (By John Emsley)

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