They have a diameter between 1nm(1x10-9) and 100nm(1x10-7)
They have a large surface area to volume ration
The surface area to volume ratio is an important factor as it can affect the way that a particles behaves
Surface area to volume ratio = surface area / volume
As particles decrease in size, the size of their surface area increases in relation to their volume, which causes the surface area to volume ratio to increase
Nanoparticles have a very high surface area to volume ratio, this means the surface area is very large compared to the volume
This can cause the properties of a material to be different depending on whether it’s a nano[article or in bulk
For example, you’ll often need less of a material that’s made up of nanoparticles to work as an effective catalyst compared to a material made up of normal sized particles(containing billions of atoms rather than a few hundred)
Comparing sizes
The table shows the sizes of nanoparticles compared to other types of particles.