What Is Nanotechnology?
Technologies are usually determined by their application relevance. Aviation technology, for example, deals with the development and improvement of aircraft. However, nanotechnology is not differentiated from other technologies by its application relevance. Rather, nanotechnology is initially only determined by the size of the materials that are being examined. In general, these are smaller than 100 nanometres up to the size of an atom.
The length designation nanometre goes back to the Greek word for dwarf. A nanometre is a billionth of a meter. Since this is hardly conceivable, one must work with a size comparison: a nanometre is to a meter like a hazelnut is to the earth. Or the diameter of a human hair is 50,000 nanometres.
Not Just Small, But Different Too
However, nanotechnology is not a separate area because everything is generally being miniaturized more and more. Computers are getting smaller, as are cell phones and their electronic components. There are already circuits that are smaller than 100 nanometres. But that is not the decisive factor.
It is crucial that the classical physical laws no longer apply below about 50 nanometres. Here the substances increasingly behave according to the laws of quantum physics. They may therefore have different optical, magnetic or electrical properties. Some light-reflecting materials, for example, become nano-sized for visible light to pass through.
An example: titanium dioxide reflects light very well. That is why it is included in wall paints and makes walls look particularly white. In contrast, nanoparticles made of titanium dioxide only reflect ultraviolet light. On the other hand, they let visible light through.
If you store titanium dioxide nanoparticles in sun creams, the cream is completely transparent and invisible on the skin. The harmful ultraviolet radiation, on the other hand, is reflected. Sun-seekers can therefore effectively protect themselves from the sun’s harmful rays without the cream being visible.
Big Surface – Big Effect
Another aspect of nanoparticles is that the surface of the material increases more and more in relation to its mass. Below 100 nanometres, the surface properties of a substance are therefore becoming increasingly important. Above all, atoms on the surface of a substance react chemically and physically with the environment and other materials.
Artificial or natural nanoparticles can act as catalysts, for example. They are also used in medicine to bring drugs to the place where they are supposed to work.