This Tech Explained focuses on nanotechnology - find out what is behind the development of molecule-sized technology.
The field of nanotechnology is often said to have been kick-started by the Nobel Prize-winning physicist Richard Feynman. In 1959, he gave a talk entitled, ‘There’s Plenty of Room at the Bottom’. Feynman speculated about the coming ability to rearrange atoms and molecules. In 1974, Japanese engineering professor Norio Taniguchi named this nascent field ‘nanotechnology’. So, what is nanotechnology and how could it affect future innovations?
Nanotechnology is the science of manipulating things on the nanoscale – at the level of molecules and atoms. While humans live on the scale of metres, atoms and molecules are measured in nanometres. A nanometre is one billionth if a metre, making the nano world one billion (1,000 million) times smaller than the world of metres.
Size is not the only difference between the world of metres and the world of nanometres. Many substances behave very differently at the atomic level. For example, carbon is normally quite soft. But if carbon atoms are tightly packed together, the resulting substance becomes very hard. Nanoparticles also have a great deal of surface area which is exposed to other nanoparticles. This makes them very good catalysts (substances that speed up chemical reactions). Forces also behave differently at this level – atoms are held together more by electromagnetic forces than by gravity.
There are clearly many possible uses for being able to manipulate and create things on the nano scale, but how can this be done? One way is by developing tools that can manipulate individual atoms and molecules. For example, a nanoscopic microscope uses electronic and quantum effects to ‘see’ individual atoms. It also contains a tiny probe that can move atoms and molecules around like tiny building blocks. Other tools include molecular beam epitaxy, in which single crystals can be grown on layer of atoms at a time.
This sounds like the stuff of science fiction, but there is a good chance that you already have products in your house that use nano technology. At Springwise, we have recently seen nanotech used in food packaging and self-cleaning fabrics. The fabrics use tiny surface fibres sometimes dubbed ‘nanograss’, which are so small that dirt particles cannot penetrate into them. This allows the deeper layers of the material to stay clean. Some sunscreens use a similar technology. They contain nano particles that block the UV rays. This type of nano particle is now also being used in scratch-resistant coatings on cars and in paints.
One of the most promising areas in nano tech are nanotubes. These are rod-shaped carbon molecules that are only around one nanometre thick. They are hollow but incredibly strong, and have excellent electrical conductivity. Their large surface areas makes them useful for absorbing pollutants and they have already been used as molecular syringes, antennas and to strengthen products like bicycle frames. The uses for nanotubes are extremely varied, and researchers are coming up with new ones all the time.
Researchers are also working on creating nano-machines and nano-robots. These could be used to build materials up atom by atom, or be injected into our bodies to repair damage from the inside. While this sounds far off, in 2016 the Nobel Prize in Chemistry was awarded to three scientists who demonstrated a technique for building nano-machines by manipulating the charge on certain molecules.
9th October 2018