Iron is an element that, in its bulk form, is used in such everyday settings as stair railings and the structural beams in cars or buildings. Iron is also present in water and in our bloodstream, where it helps to transport oxygen. Iron is one of the materials that we can use to make magnets due to the way electrons orbit each atom. And, as we all know, iron rusts when you combine iron and oxygen to form iron oxide. It turns out that nanoparticles of both iron and iron oxide can be quite useful.
All electrons spin; this is a fact of life. A magnet is formed by aligning the spin of unpaired electrons to a magnetic field. Each iron atom has four unpaired electrons arranged around each atom, which means they can be aligned to turn any piece of iron into a magnet.
Iron nanoparticles also retain iron’s magnetic properties. What’s interesting is that, like iron oxide, these magnetic nanoparticles have increased surface area. This allows the iron nanoparticles to be useful in both medical imaging and cleaning up pollutants in groundwater.
Researchers are investigating the use of iron nanoparticles as the next step beyond iron oxide nanoparticles for medical imaging and treatments such as the following:
Iron nanoparticles are also useful in cleaning up organic pollutants in groundwater because they can donate electrons to more electronegative atoms, such as chlorine atoms, present in many of the molecules that make up organic pollutants. Donating these electrons can cause the molecules to break up into harmless molecules. Because nanoparticles can remain suspended in groundwater for a long time and are transported throughout the system, they are used to treat large areas of groundwater.
Excerpted from Nanotechnology For Dummies (2nd edition), from Wiley Publishing