What is Nanotechnology?


C60 containing heavy metal atom (c)Chris EwelsNanoscience is the study of the very small - things at the nanometer scale. This is the scale of large molecules; molecular chains (like plastics), proteins (from biology), nano-crystals (for example nanocrystalline diamond) and new large molecules like fullerenes and nanotubes. Nanoscience is essentially the physics and chemistry of objects at the nanoscale.

Don't believe it if you hear the laws of physics no longer apply at this scale - they certainly do! However they sometimes behave differently to what we're used to at the human scale of things. For example, just as if you look closely at a newspaper picture it starts to look like lots of dots, so energies at the nanoscale and smaller can become quantised (split into certain fixed amounts). As crystals get smaller the ratio of their surface area to volume increases - many nano-objects are all surface (all skin and no custard!). This can be a useful property for catalysts, where chemical reactions occur on their surfaces (nano-scale catalysts can be extremely efficient).

If you want to find out more about nanoscience and nanoscale objects, I have a new page of nanoscience related web links. Otherwise here are a few of them you might want to try:

A la découverte du Nanomonde (en Français)
pdf brochure in French describing current research into nanoscience and nanotechnology with good introduction describing the nanoscale.

Nano white papers
Executive summaries covering many new nanomaterials and the current state of nanoscience.

The Next Big Thing - Nanotechnology
An on-line video from the Vega Science Trust where some of the world's top nanoscientists discuss what it is and where it may be leading.

What is a carbon nanotube?

A carbon nanotube is a large molecule made of carbon atoms. The atoms are arranged in hexagons, much like chicken wire, the same arrangement as in graphite. However in graphite this 'chicken wire' lies in flat sheets on top of each other - in a nanotube the sheet is curled up into a tube. Why does it do this? Because the carbon atoms at the edge of the sheet of graphite don't have enough carbon neighbours; by forming a tube the edges are removed. You can see these different structures here (note that a nanotube doesn't really form by curling up in this way - they form directly as tubes from their constituent carbon atoms - this is just an easier way to see how graphite and carbon nanotubes are related).
Flat sheet of graphite Flat sheet of graphite Flat sheet of graphite
Flat sheet of Graphite Partially rolled sheet of graphite A carbon nanotube
Notice that you have a choice over how you roll up the graphite sheet, depending on whether you connect together the top and bottom edges, or the left and right; the same occurs in nature and the resultant nanotubes have different electrical properties. You can also attach the edges directly or offset them, making a helical tube. (you can see these variations with a sheet of paper).

If you want to see more objects from the nanoscale, feel free to have a look around my nanoscience image gallery. All images ©2003 Chris Ewels, please do not use without permission.


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Last modified November 7, 2006