Nanofuses?

I thought this was kind of cool.

http://news.bbc.co.uk/1/hi/sci/tech/8556656.stm

Nanotubes, you say?

Well, maybe I should add some context to this

Elemental materials are substance completely composed of one type (element) of atom. Despite this, there are a couple of elemental materials that come in different forms, with very different structures and properties. This phenomenon is called allotropy and the best example are materials made of carbon. You will have come across two most common allotropes of carbon: graphite and diamond. Graphite is the materials in pencils often mistaken for ‘lead’ i.e. the part that makes the marks. Diamonds, well diamonds are those sparkly things you put on rings when you want someone to marry you. Thinking about those examples should be enough to illustrate, just how different things made from the same atoms can be.

The carbon atoms in graphite are joined together in six-sided rings which are all then joined together to make large, flat sheets of carbon. Graphite, in its purest form, is made up of millions upon millions of these sheets stacked on top each other like the pages in a book. However, they are interesting in nanotechnology because of what happens when you start to play with one of these pages (a single sheet is called graphene and is attracting a lot of interest of it own).

The products of this “carbon sheet origami” are called fullerenes. These molecules are the third allotrope of carbon and they are fast becoming the workhorses of nanotechnology.

With the right conditions and adding a bit of energy, usually in the form of a large electric spark, it is possible to make these sheets roll themselves into balls. The result is a hollow sphere made out of interlocking carbon rings. It’s easy to get the idea if you to try to picture the way hexagonal patches are glued together on the outside of a football (soccerball). This is a fullerene.  The first discovered and most common variety is ‘Buckminster fullerene’ a.k.a the ‘buckyball‘. Coming in at around 1 nm wide, buckyballs are large as molecules go but small for nanomaterials.

It is also possible to roll the sheet up into a cylinder like a paper straw, and this is called a carbon nanotube. These materials have been found to have some amazing properties such as being able to conduct heat and electricity in interesting new ways, and they are far stronger than steel when pulled, in fact they have the highest tensile strength of any material discovered so far.

So there we go, dipping our toes into the world of carbon nanomaterials. Trust me these little things are important and I believe they’ll be making a huge impact in future technologies.

Oh and graphite is one of the easier materials to do fancy microscopy on. When I say fancy, I mean seeing the ACTUAL ATOMS of the carbon rings. It easy to see such images if you google for ‘graphite’ and either ‘scanning tunnelling microscope’ or ‘atomic force microscope’. This one is from the Institut fur Physik, the University of Augsburg, Germany.

 

  

There are days when I am still gobsmacked by the fact that we humans, the hairless, fart-joke obsessed apes we are, have managed to find a way to take photographs of ACTUAL ATOMs. Even after four years of being the one taking those pictures I stil feel that way and hope I never stop.

 

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