Nanomaterials are an increasingly important product of nanotechnologies. They contain nanoparticles, smaller than 100 nanometres in at least one dimension. A nanometer is one millionth of a millimeter – approximately 100,000 times smaller than the diameter of a human hair.
Nano-sized particles exist in nature and can be created from a variety of products, such as carbon or minerals like silver, but nanomaterials by definition must have at least one dimension that is less than approximately 100 nanometers. Most nanoscale materials are too small to be seen with the naked eye and even with conventional lab microscopes.
Materials engineered to such a small scale are often referred to as engineered nanomaterials (ENMs), which can take on unique optical, magnetic, electrical, and other properties. These emergent properties have the potential for great impacts in electronics, medicine, and other fields.