Showing posts with label materials. Show all posts
Showing posts with label materials. Show all posts

Thursday, 13 June 2013

Graphene Part II - The Thrilling Conclusion

If I wanted to write an exhaustive article about everything scientists have proposed using graphene for, I would be typing for a long time. There are encyclopedic websites that you can go to if you want to spend the next several weeks reading about graphene-based bomb detectors or how to give your car the greatest rust-proofing in the universe. Instead I’m going to spell out the 5 uses of graphene that I think are the most amazing and most likely to change the world:

1) Super-capacitors

A capacitor is a device that can take the place of a battery and power a piece of electronic equipment using energy stored in carbon. The problem with capacitors for a long time has been that they don’t hold much of a charge per unit of weight. The thing about graphene is that it is ridiculously light (0.77 grams per meter squared) and has a maximum surface area that anything can have.

Imagine electrons as tennis balls, and imagine the carbon inside of a capacitor as a cube that is coated in Velcro. You can stick a certain number of tennis balls onto your Velcro cube, but eventually you’re going to run out of space. If you cut the cube in half, you increase its surface area and you can attach a few more tennis balls. Now imagine that you were able to cut the cube into sheets that were one atom thick (minus the Velcro). If your original cube was 1mX1mX1m, you would need about 1.5 trillion tennis balls to cover all of your single-atom sheets. That’s a lot of tennis balls. That’s translates into a lot of electrons, and a lot of stored energy. A superconductor using graphene would be able to recharge in minutes or seconds and last for an impossibly long time. Imagine an electric car that you could recharge in 5 minutes and drive for a few weeks in between charges. That would change the world.




2) Fuel Cells

This one is pretty similar to supercapacitors, except replace electrons/tennis balls with hydrogen. Hydrogen can bind with the carbon in graphene and be used to fuel cars. Since graphene is lightweight and has incredible surface area, a fuel cell that incorporates graphene as a binding agent could make fuel celled cars a practical reality.



3) Lightning-Fast Circuits

Graphene is able to conduct electricity amazingly well. It’s super-fast and super-efficient. It has also been experimentally used to create circuit boards that could make a laptop 50 times faster and never need a cooling fan. The coolest part? Some people think that graphene circuit boards could be on the market in as little as 5 years.

4) Solar Cells

As we now know, graphene is the Rolls Royce of electrical conduction. That translates into awesome potential for things like solar panels. A panel that used graphene as its conductor and carbon nanotubes (CNT's) to absorb light and transfer electrons would be cheaper, lighter, and faster than anything we can conceive of today. Imagine driving your supercapacitor car with a graphene solar panel on the roof constantly recharging it. Road trip, anyone?




5) Disease Diagnostics

Last but not least, there is the potential to use graphene to diagnose diseases. This takes a bit of explaining, but if you’ve read this far it’s probably safe to say you’re at least vaguely interested. First off, graphene is able to bind with certain molecules that are sensitive to various diseases, call these “fluorescent molecules.” These molecules can also bind with DNA. If you want to make a graphene sensor for detecting disease, you take some DNA with markers for that disease and bind it with some fluorescent molecules. Then you bind your wacky DNA-fluorescent molecule to a piece of graphene. Next, take your sensor and put it in a science-type beaker with a DNA sample from a sick person. When a piece of DNA with the same markers as the DNA on the graphene floats by, it sticks to the sensor and creates a double-strand of DNA. The double strand breaks away and can be detected by looking for the fluorescent molecules. The awesome thing about graphene is that its incredible surface area allows you to test for an incredible amount of diseases at the same time. Imagine being able to test for every kind of cancer known to man simultaneously and to detect the disease at its earliest stages. Sign me up.




So there it is. Call me an optimist, but I can’t wait to fly by Geoff’s house in my supercapacitor powered car, blasting music from my iPod that never runs out of battery, on my way to the other side of the country, on my 150th birthday, without stopping to recharge. I’ll toss him a shirt that says “I was totally wrong.”



Wednesday, 12 June 2013

Graphene: The Wonder Material to Save the World Part I

The decision to start this blog grew somewhat organically from many conversations my illustrator and I have had about various new discoveries across the realm of science. Our conversations usually build from a shared curiosity and one of us understanding something better than the other and being willing to explain it. There is one topic though, where we have continuously butt heads: graphene. I am always amazed and optimistic about the possibilities that might come from research into this so-called “wonder material,” while Geoff (who works in the field of nanotechnology) thinks graphene is the most over-hyped thing since those people who were in Twilight broke up. This week's discussion is an attempt to share our incessant bickering with you, avid reader. Now let’s get on with it!




Intro!

So first off, what is graphene anyway? The average person who doesn’t seek out science news on a regular basis could be forgiven for never having heard of it. Right now, it’s a bit of a niche material, but one day it will probably change your life.

When you get right down to it, graphene is the world’s first 2-dimensional anything. It is as thin as thin can be – a single atom thick. To put that in perspective, aluminum foil is about 193,000 atoms thick. A human hair is between 100,000 and 200,000 atoms in diameter. Graphene, in other words, is crazy thin. It is also made entirely of carbon, making it something like an infinitely squished diamond.




Graphene was discovered, as all great things in science are, by a couple guys screwing around with lab equipment. One day in 2004, Andrei Geim and Kostya Novoselov, a pair of Russian researchers working at the University of Manchester, decided to see what would happen if they took a piece of Scotch tape and used it to peel layers off of a piece of graphite. They weren’t the first people to do this (Scotch tape is commonly used by researchers to clean up a piece of graphite before putting it under a lens), but Geim and Novoselov where the first people to take it somewhat too far. They peeled and peeled flakes of graphite until they were left with a sheet only a couple atoms thick. From there, they used scientific ingenuity to transfer the bits they had left onto a silicon wafer and won themselves the Nobel Prize in Physics in 2010.





Now you might be wondering why they would get a Nobel prize for that. Sure making the thinnest thing physically possible is pretty cool. It might even be worthy of free pints for life at the university pub, but a Nobel Prize? The answer lies in the doors their research opened up for science and technology. They didn’t just make something one-atom thick, they made it out of pure carbon; and, as we will see in Part II of this post, carbon is pretty awesome stuff.

Come back tomorrow for the thrilling conclusion... (Geoff is drawing as we speak).